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What Can We Hear?
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Gary Eickmeier
May 14, 2012, 7:44:59 PM5/14/12
to
There are lots and lots of discussions and descriptions of what we can hear
in the subjective press and in these halls of RAHE. Some of these
descriptions go into detail that is sometimes real, sometimes imagined,
leading to wild arguments about double blind listening tests vs subjectivism
and long experience. I think most of it misses the main points of genuine
"hard-nosed" listening and being honest with yourself about what you are
really hearing with your system. I mean, like, you want to think that your
speakers or whatever are better than they are, or that your ears and tastes
are so sophisticated that you can hear all of these marvelous aspects of
recorded sound - and you hope that the rest of us will believe you, that
either your hearing is so much better than ours, or your components are
"revealing" so much more due to their greater "accuracy."
So let's cut the bullshit and ask ourselves what CAN we really hear about
the original live sound and the reproduction, and thus what kind of
correlation can we draw between them to possibly see how far we have come,
or how far we can go. I struggle to come up with a catchy name for these
characteristics, but for now let's all them the Essential Elements of
Fidelity, or EEF.
THE ESSENTIAL ELEMENTS OF FIDELITY
OK, everybody stand up and shake your hands, wiggle you ears and noses,
whatever it takes to shake off all preconceptions of "inner detail," "phase
anomolies," "transient response," "togetherness," "toe tapping ability (my
personal favorite)," or any of the many other supposedly audible
characteristics of reproduced sound and let's start over again.
1. PHYSICAL SIZE - whether you're talking about the real thing or the
reproduction, we can hear the size of a room we are in. This is due to the
time between reflections, the characteristics of the reverberant tail, and
maybe some discrete echoes, which good spaces shouldn't have, but in any
case we can tell whether we are in a big or a small room. In the
reprocuction, one of the main problems is that the acoustics of the repro
room are superimposed on those of the recording, and we can sense that
fairly easily. This means, the larger you can design your room, the more
realistic it will sound, because it will be more like the real thing. It
also does away with some other pesky acoustical problems at the same time,
but right now I just want to point our that physical size is audible.
2. POWER - of course we can hear the enormous power of a symphony orchestra
or a big band, or even a smaller group. This means that the more power we
have in the reproduction, the closer to realism we will get. You can have
great fidelity in a boombox or a desktop computer speaker system, but it
will not have the POWER of the real thing unless and until you get some
speakers that can take any amount of power you can give them and get louder
without distorting, and amplifiers that have that power rather than the
audiophile fave raves of dainty 20W tube amps. Power is definitely audible.
3. WAVEFORM FIDELITY - I have been taken to task for calling it that,
because the actual shape of a waveform is not the point, but I can't think
of a term to describe what I mean by just simply the accuracy in the
electronic domain of the recorded signal transmission. This includes, of
course, frequency response, noise, and distortion. We struggled with these
for a long time in our audio history with LP records and magnetic tape. But
now with digital, we have essentially eliminated this characteristic from
being a problem in recording or reproduction. Still, it is one of the
factors that we can hear, so I list it for completeness.
4. SPATIAL CHARACTERISTICS - This is the biggie, the collective term for
the realistic reproduction of auditory perspective - the stereo effect and
all of the possible recording and reproduction systems and schemes. But for
now, all we need to point out is that we can hear the spatial
characteristics of live and reproduced sound, and those characteristics are
very important to both the enjoyment of live sound (and quality of a concert
hall) and the realism of the reproduction.
Now, not to impugn your intelligence or vast knowledge, if most of us think
we understand what this spatial stuff is all about, but to emphasize the
difference between the spatial and the temporal, the two aspects of a sound
field that get continually confused with each other, I would like to add an
illustration.
Your friend is a novice audiophile on his way back from Best Buy, where he
has purchased a new home theater system and learned all about hi fi from the
salesman. He sets up the speakers all up front, perhaps all in a row or all
on top of his "teevee" and he plays a movie or some music. It is very
accurate, plays all of the frequencies and the timings of the ambience that
were recorded, but it just doesn't sound realistic yet. So you go over and
show him how to correctly place all of the speakers to reconstruct a
semblance of the sound field that was recorded in his listening room. You
place the front speakers LCR for correct perspective of the frontal
soundstage, and you place the surround speakers back and to the sides, where
the ambience of the hall should come from. You have addressed the SPATIAL
characteristic, which has nothing to do with the temporal, but rather with
the directions form which the various sound fields arrive at the listener,
or exist in the listening room. I bring this up because of a frequent
question about my statements on getting the spatial more correct. They
always tell me that getting the spatial more correct can't work because you
can't make a small room sound like a concert hall. They have confused, or
"fused" the spatial and the temporal.
So I try to explain the difference but for now I only want to state that
these are the main characteristics of sound that we can hear and try to
reproduce. Do you have any other "biggies" that I have left out? I would be
fascinated.
So what is the state of the art of attempts to reproduce all of these and
how far can we go?
The physical size and waveform accuracy and power we can easily get a handle
on and improve, if for example we are in a small room and we understand that
limitation. The spatial stuff is the biggie and is where I say we need more
basic understanding of the process in order to get any further than we have
already come in 100 or so years.
The most basic and foolish mislead is thinking that good "stereo" comes from
the direct sound alone, and trying to kill the room reflections or design a
speaker that casts all of its sound toward your hapless ears. This
misconception, or mislead, is caused by the confusion between stereo and
binaural.
Stereo does not work like a "window into another acoustic." Rather, if you
think of it as a model of the original, in which your room is the performing
space and your speaker setup attempts to get the spatial closer to the
original, then you have a fighting chance for greater realism, but you also
inherit the understanding that it is not an "accuracy" process, and we can
never get all the way there. We cannot, in other words, totally get to the
goal of a "you are there" experience but rather more like a "they are here"
experience in which your room is the performing space and you design it for
good sound and arrange THE BIG THREE of speaker positioning, radiation
pattern, and room acoustics to get the model closer to the live situation.
So what can we hear? We can hear the spatial, spectral, and temporal
characteristics of our listening room and speaker situation, or layout,
superimposed on that of the recording, and we can hear the physical size,
power, and electronic accuracy of your system. When we play back any
recording, we CHANGE the spatial characteristics of the original to those of
our playback system and room.
That is slightly too bad, but once we understand the limitations of the
system and what can be achieved, we can stop worrying about false goals and
start concentrating on more fruitful paths that can lead to greater realism.
Gary Eickmeier
in the subjective press and in these halls of RAHE. Some of these
descriptions go into detail that is sometimes real, sometimes imagined,
leading to wild arguments about double blind listening tests vs subjectivism
and long experience. I think most of it misses the main points of genuine
"hard-nosed" listening and being honest with yourself about what you are
really hearing with your system. I mean, like, you want to think that your
speakers or whatever are better than they are, or that your ears and tastes
are so sophisticated that you can hear all of these marvelous aspects of
recorded sound - and you hope that the rest of us will believe you, that
either your hearing is so much better than ours, or your components are
"revealing" so much more due to their greater "accuracy."
So let's cut the bullshit and ask ourselves what CAN we really hear about
the original live sound and the reproduction, and thus what kind of
correlation can we draw between them to possibly see how far we have come,
or how far we can go. I struggle to come up with a catchy name for these
characteristics, but for now let's all them the Essential Elements of
Fidelity, or EEF.
THE ESSENTIAL ELEMENTS OF FIDELITY
OK, everybody stand up and shake your hands, wiggle you ears and noses,
whatever it takes to shake off all preconceptions of "inner detail," "phase
anomolies," "transient response," "togetherness," "toe tapping ability (my
personal favorite)," or any of the many other supposedly audible
characteristics of reproduced sound and let's start over again.
1. PHYSICAL SIZE - whether you're talking about the real thing or the
reproduction, we can hear the size of a room we are in. This is due to the
time between reflections, the characteristics of the reverberant tail, and
maybe some discrete echoes, which good spaces shouldn't have, but in any
case we can tell whether we are in a big or a small room. In the
reprocuction, one of the main problems is that the acoustics of the repro
room are superimposed on those of the recording, and we can sense that
fairly easily. This means, the larger you can design your room, the more
realistic it will sound, because it will be more like the real thing. It
also does away with some other pesky acoustical problems at the same time,
but right now I just want to point our that physical size is audible.
2. POWER - of course we can hear the enormous power of a symphony orchestra
or a big band, or even a smaller group. This means that the more power we
have in the reproduction, the closer to realism we will get. You can have
great fidelity in a boombox or a desktop computer speaker system, but it
will not have the POWER of the real thing unless and until you get some
speakers that can take any amount of power you can give them and get louder
without distorting, and amplifiers that have that power rather than the
audiophile fave raves of dainty 20W tube amps. Power is definitely audible.
3. WAVEFORM FIDELITY - I have been taken to task for calling it that,
because the actual shape of a waveform is not the point, but I can't think
of a term to describe what I mean by just simply the accuracy in the
electronic domain of the recorded signal transmission. This includes, of
course, frequency response, noise, and distortion. We struggled with these
for a long time in our audio history with LP records and magnetic tape. But
now with digital, we have essentially eliminated this characteristic from
being a problem in recording or reproduction. Still, it is one of the
factors that we can hear, so I list it for completeness.
4. SPATIAL CHARACTERISTICS - This is the biggie, the collective term for
the realistic reproduction of auditory perspective - the stereo effect and
all of the possible recording and reproduction systems and schemes. But for
now, all we need to point out is that we can hear the spatial
characteristics of live and reproduced sound, and those characteristics are
very important to both the enjoyment of live sound (and quality of a concert
hall) and the realism of the reproduction.
Now, not to impugn your intelligence or vast knowledge, if most of us think
we understand what this spatial stuff is all about, but to emphasize the
difference between the spatial and the temporal, the two aspects of a sound
field that get continually confused with each other, I would like to add an
illustration.
Your friend is a novice audiophile on his way back from Best Buy, where he
has purchased a new home theater system and learned all about hi fi from the
salesman. He sets up the speakers all up front, perhaps all in a row or all
on top of his "teevee" and he plays a movie or some music. It is very
accurate, plays all of the frequencies and the timings of the ambience that
were recorded, but it just doesn't sound realistic yet. So you go over and
show him how to correctly place all of the speakers to reconstruct a
semblance of the sound field that was recorded in his listening room. You
place the front speakers LCR for correct perspective of the frontal
soundstage, and you place the surround speakers back and to the sides, where
the ambience of the hall should come from. You have addressed the SPATIAL
characteristic, which has nothing to do with the temporal, but rather with
the directions form which the various sound fields arrive at the listener,
or exist in the listening room. I bring this up because of a frequent
question about my statements on getting the spatial more correct. They
always tell me that getting the spatial more correct can't work because you
can't make a small room sound like a concert hall. They have confused, or
"fused" the spatial and the temporal.
So I try to explain the difference but for now I only want to state that
these are the main characteristics of sound that we can hear and try to
reproduce. Do you have any other "biggies" that I have left out? I would be
fascinated.
So what is the state of the art of attempts to reproduce all of these and
how far can we go?
The physical size and waveform accuracy and power we can easily get a handle
on and improve, if for example we are in a small room and we understand that
limitation. The spatial stuff is the biggie and is where I say we need more
basic understanding of the process in order to get any further than we have
already come in 100 or so years.
The most basic and foolish mislead is thinking that good "stereo" comes from
the direct sound alone, and trying to kill the room reflections or design a
speaker that casts all of its sound toward your hapless ears. This
misconception, or mislead, is caused by the confusion between stereo and
binaural.
Stereo does not work like a "window into another acoustic." Rather, if you
think of it as a model of the original, in which your room is the performing
space and your speaker setup attempts to get the spatial closer to the
original, then you have a fighting chance for greater realism, but you also
inherit the understanding that it is not an "accuracy" process, and we can
never get all the way there. We cannot, in other words, totally get to the
goal of a "you are there" experience but rather more like a "they are here"
experience in which your room is the performing space and you design it for
good sound and arrange THE BIG THREE of speaker positioning, radiation
pattern, and room acoustics to get the model closer to the live situation.
So what can we hear? We can hear the spatial, spectral, and temporal
characteristics of our listening room and speaker situation, or layout,
superimposed on that of the recording, and we can hear the physical size,
power, and electronic accuracy of your system. When we play back any
recording, we CHANGE the spatial characteristics of the original to those of
our playback system and room.
That is slightly too bad, but once we understand the limitations of the
system and what can be achieved, we can stop worrying about false goals and
start concentrating on more fruitful paths that can lead to greater realism.
Gary Eickmeier
Audio Empire
May 15, 2012, 7:47:21 PM5/15/12
to
On Mon, 14 May 2012 16:44:59 -0700, Gary Eickmeier wrote
(in article <jos5d...@news3.newsguy.com>):
> There are lots and lots of discussions and descriptions of what we can hear
> in the subjective press and in these halls of RAHE. Some of these
> descriptions go into detail that is sometimes real, sometimes imagined,
> leading to wild arguments about double blind listening tests vs subjectivism
> and long experience. I think most of it misses the main points of genuine
> "hard-nosed" listening and being honest with yourself about what you are
> really hearing with your system. I mean, like, you want to think that your
> speakers or whatever are better than they are, or that your ears and tastes
> are so sophisticated that you can hear all of these marvelous aspects of
> recorded sound - and you hope that the rest of us will believe you, that
> either your hearing is so much better than ours, or your components are
> "revealing" so much more due to their greater "accuracy."
>
> So let's cut the bullshit and ask ourselves what CAN we really hear about
> the original live sound and the reproduction, and thus what kind of
> correlation can we draw between them to possibly see how far we have come,
> or how far we can go. I struggle to come up with a catchy name for these
> characteristics, but for now let's all them the Essential Elements of
> Fidelity, or EEF.
The human ear is a sensitive tool, no doubt about it. Unfortunately, it is
also an interpretive tool. There is no sound preception without the brain and
the brain brings with it a lifetime of experience, preconceptions, and
personal preferences. It applies these factors to everything we hear and
they're difficult to overcome. In fact, I'd go so far as to say that we, as
individuals, can't overcome them. We are going to hear what we want to hear
or what we expect to hear. The only way around this is to take human bias out
of the equation with tests that are either totally objective (such as
measurements using instrumentation) or by taking part in listening tests
which remove as much of the human propensity for self-delusion as possible
and relying on the statistical results. To paraphrase an old adage: he who
trusts his own ear/brain interface to judge audio qualities is a fool.
> THE ESSENTIAL ELEMENTS OF FIDELITY
>
> OK, everybody stand up and shake your hands, wiggle you ears and noses,
> whatever it takes to shake off all preconceptions of "inner detail," "phase
> anomolies," "transient response," "togetherness," "toe tapping ability (my
> personal favorite)," or any of the many other supposedly audible
> characteristics of reproduced sound and let's start over again.
Phase anomalies are real. You can measure them and you can easily hear their
effects. All one has to do is walk past a stereo pair of speakers that are
wired out-of phase to instantly hear the results. You can also take a
recording made with a pair of spaced omnis and sum the two channels to mono
to immediately hear (and see, on an oscilloscope) some of the instruments go
away.
> 1. PHYSICAL SIZE - whether you're talking about the real thing or the
> reproduction, we can hear the size of a room we are in. This is due to the
> time between reflections, the characteristics of the reverberant tail, and
> maybe some discrete echoes, which good spaces shouldn't have, but in any
> case we can tell whether we are in a big or a small room. In the
> reprocuction, one of the main problems is that the acoustics of the repro
> room are superimposed on those of the recording, and we can sense that
> fairly easily. This means, the larger you can design your room, the more
> realistic it will sound, because it will be more like the real thing. It
> also does away with some other pesky acoustical problems at the same time,
> but right now I just want to point our that physical size is audible.
I have to disagree here. While you are correct about being able to tell, even
blindfolded, the approximate size of a room you're in, you are wrong about
the results. It is possible to make a small room sound good much more easily
than it is possible to make a large room sound good. Small rooms have all the
characteristics that you mention (and then some) but they are all fairly
controllable.
> 2. POWER - of course we can hear the enormous power of a symphony orchestra
> or a big band, or even a smaller group. This means that the more power we
> have in the reproduction, the closer to realism we will get. You can have
> great fidelity in a boombox or a desktop computer speaker system, but it
> will not have the POWER of the real thing unless and until you get some
> speakers that can take any amount of power you can give them and get louder
> without distorting, and amplifiers that have that power rather than the
> audiophile fave raves of dainty 20W tube amps. Power is definitely audible.
Again you are grossly oversimplifying. Power, in and of itself is merely a
means to an end. The end is moving air. The more air you can move the more
realistically an audio system will load the room with sound and the amount of
air any speaker can move with a Watt of electrical power from an amplifier is
determined by two things: the efficiency of the speaker and the volume of the
space one is trying to fill. The most realistic reproduction of the POWER of
a symphony orchestra I ever heard was from a pair of the big Klipschorn
corner horns in a smallish basement listening room in the early 1960's. The
system was owned by a high-school buddy of mine's dad. The effect was jaw
dropping. Here was a small pair of Heathkit Williamson power amps at about 25
Watts each that would drive these speakers to pump-out so much air, that,
like sitting front row center in a concert hall, while the NY Philharmonic
plays the climax or Ravel's "Bolero" , it literally made one's pants legs
flap with the music!. These speakers were so efficient, that you could play
them loud enough to have to scream to be heard over them with just the
earphone output of a garden-variety Japanese transistor radio, of the type
every teen carried around with him in those days. The Klipshorns were 50%
efficient. That meant that every two Watts of amplifier power produced one
acoustic Watt of sound (One acoustic Watt is defined as being equivalent to
107.5 dBSPL at around a meter from an omnidirectional source)! Of course,
most speakers are nowhere near that efficient and it can often take more than
100 electrical Watts to produce one Acoustic Watt at one meter. That would
make those speakers 1% efficient. Now, since sound pressure dissipates at a
rate inversely proportional to the distance one is from the speakers,
obviously, the larger the room, the more power it takes to maintain a
realistic sound power level in that room. After all, few people sit one meter
of less from their speakers. The point here is it's not the power itself
that's important, it's the amount of power the SPEAKERS need to reproduce the
SPL necessary to achieve the desired room loading. Some speakers can do it
with a 10 Watt SET amp and some require many hundreds of Watts for the same
effect. Now, understand, that we are talking about ONE and only one parameter
here. That's acoustical energy or volume. We aren't talking about frequency
response or imaging or any other sound characteristic. Fact is that while
Klipschorns were certainly realistically loud, they were not particularly
great sounding. They didn't have much bass below 50 Hz, and they certainly
weren't flat over the rest of the sdpectrum. I wouldn't want a pair in my
system, but at the time, when a 10 Watt amplifier was the norm, and a 25 Watt
amp was a behemoth, they produced the SPL that many audiophiles were looking
for.
> 3. WAVEFORM FIDELITY - I have been taken to task for calling it that,
> because the actual shape of a waveform is not the point, but I can't think
> of a term to describe what I mean by just simply the accuracy in the
> electronic domain of the recorded signal transmission. This includes, of
> course, frequency response, noise, and distortion. We struggled with these
> for a long time in our audio history with LP records and magnetic tape. But
> now with digital, we have essentially eliminated this characteristic from
> being a problem in recording or reproduction. Still, it is one of the
> factors that we can hear, so I list it for completeness.
Try "source signal accuracy." 8^)
Again, I disagree. Binaural sound only works with headphones. Stereo is
designed for speakers. Hall ambience can be captured by the recording
microphones, or it can be captured by an auxiliary pair of mikes placed at
some distance in the room away from the musicians. It can also be
artificially created and added either at the recording end of the chain, or
the playback end.
> Stereo does not work like a "window into another acoustic."
Actually, it is a pair of windows (in a traditional two-channel stereo
setup). They're called your speakers. Their job is to recreate, as accurately
as possible, the electrical signal fed to them. Ideally, the acoustic
wavefront they produce will be exactly like the audio signal they are fed.
The problem is that's an illusive goal. It's pretty much impossible, in fact.
We can get close, and we DO get closer all the time. but each step we take
toward that goal, gets smaller than the one before it. Taken metaphorically,
we'll never get there.
Rather, if you
> think of it as a model of the original, in which your room is the performing
> space and your speaker setup attempts to get the spatial closer to the
> original, then you have a fighting chance for greater realism, but you also
> inherit the understanding that it is not an "accuracy" process, and we can
> never get all the way there. We cannot, in other words, totally get to the
> goal of a "you are there" experience but rather more like a "they are here"
> experience in which your room is the performing space and you design it for
> good sound and arrange THE BIG THREE of speaker positioning, radiation
> pattern, and room acoustics to get the model closer to the live situation.
And this would be different from two open windows onto a space where a
musical ensemble is playing, how?
> So what can we hear? We can hear the spatial, spectral, and temporal
> characteristics of our listening room and speaker situation, or layout,
> superimposed on that of the recording, and we can hear the physical size,
> power, and electronic accuracy of your system. When we play back any
> recording, we CHANGE the spatial characteristics of the original to those of
> our playback system and room.
>
> That is slightly too bad, but once we understand the limitations of the
> system and what can be achieved, we can stop worrying about false goals and
> start concentrating on more fruitful paths that can lead to greater realism.
Which would be?
(in article <jos5d...@news3.newsguy.com>):
> There are lots and lots of discussions and descriptions of what we can hear
> in the subjective press and in these halls of RAHE. Some of these
> descriptions go into detail that is sometimes real, sometimes imagined,
> leading to wild arguments about double blind listening tests vs subjectivism
> and long experience. I think most of it misses the main points of genuine
> "hard-nosed" listening and being honest with yourself about what you are
> really hearing with your system. I mean, like, you want to think that your
> speakers or whatever are better than they are, or that your ears and tastes
> are so sophisticated that you can hear all of these marvelous aspects of
> recorded sound - and you hope that the rest of us will believe you, that
> either your hearing is so much better than ours, or your components are
> "revealing" so much more due to their greater "accuracy."
>
> So let's cut the bullshit and ask ourselves what CAN we really hear about
> the original live sound and the reproduction, and thus what kind of
> correlation can we draw between them to possibly see how far we have come,
> or how far we can go. I struggle to come up with a catchy name for these
> characteristics, but for now let's all them the Essential Elements of
> Fidelity, or EEF.
also an interpretive tool. There is no sound preception without the brain and
the brain brings with it a lifetime of experience, preconceptions, and
personal preferences. It applies these factors to everything we hear and
they're difficult to overcome. In fact, I'd go so far as to say that we, as
individuals, can't overcome them. We are going to hear what we want to hear
or what we expect to hear. The only way around this is to take human bias out
of the equation with tests that are either totally objective (such as
measurements using instrumentation) or by taking part in listening tests
which remove as much of the human propensity for self-delusion as possible
and relying on the statistical results. To paraphrase an old adage: he who
trusts his own ear/brain interface to judge audio qualities is a fool.
> THE ESSENTIAL ELEMENTS OF FIDELITY
>
> OK, everybody stand up and shake your hands, wiggle you ears and noses,
> whatever it takes to shake off all preconceptions of "inner detail," "phase
> anomolies," "transient response," "togetherness," "toe tapping ability (my
> personal favorite)," or any of the many other supposedly audible
> characteristics of reproduced sound and let's start over again.
effects. All one has to do is walk past a stereo pair of speakers that are
wired out-of phase to instantly hear the results. You can also take a
recording made with a pair of spaced omnis and sum the two channels to mono
to immediately hear (and see, on an oscilloscope) some of the instruments go
away.
> 1. PHYSICAL SIZE - whether you're talking about the real thing or the
> reproduction, we can hear the size of a room we are in. This is due to the
> time between reflections, the characteristics of the reverberant tail, and
> maybe some discrete echoes, which good spaces shouldn't have, but in any
> case we can tell whether we are in a big or a small room. In the
> reprocuction, one of the main problems is that the acoustics of the repro
> room are superimposed on those of the recording, and we can sense that
> fairly easily. This means, the larger you can design your room, the more
> realistic it will sound, because it will be more like the real thing. It
> also does away with some other pesky acoustical problems at the same time,
> but right now I just want to point our that physical size is audible.
blindfolded, the approximate size of a room you're in, you are wrong about
the results. It is possible to make a small room sound good much more easily
than it is possible to make a large room sound good. Small rooms have all the
characteristics that you mention (and then some) but they are all fairly
controllable.
> 2. POWER - of course we can hear the enormous power of a symphony orchestra
> or a big band, or even a smaller group. This means that the more power we
> have in the reproduction, the closer to realism we will get. You can have
> great fidelity in a boombox or a desktop computer speaker system, but it
> will not have the POWER of the real thing unless and until you get some
> speakers that can take any amount of power you can give them and get louder
> without distorting, and amplifiers that have that power rather than the
> audiophile fave raves of dainty 20W tube amps. Power is definitely audible.
means to an end. The end is moving air. The more air you can move the more
realistically an audio system will load the room with sound and the amount of
air any speaker can move with a Watt of electrical power from an amplifier is
determined by two things: the efficiency of the speaker and the volume of the
space one is trying to fill. The most realistic reproduction of the POWER of
a symphony orchestra I ever heard was from a pair of the big Klipschorn
corner horns in a smallish basement listening room in the early 1960's. The
system was owned by a high-school buddy of mine's dad. The effect was jaw
dropping. Here was a small pair of Heathkit Williamson power amps at about 25
Watts each that would drive these speakers to pump-out so much air, that,
like sitting front row center in a concert hall, while the NY Philharmonic
plays the climax or Ravel's "Bolero" , it literally made one's pants legs
flap with the music!. These speakers were so efficient, that you could play
them loud enough to have to scream to be heard over them with just the
earphone output of a garden-variety Japanese transistor radio, of the type
every teen carried around with him in those days. The Klipshorns were 50%
efficient. That meant that every two Watts of amplifier power produced one
acoustic Watt of sound (One acoustic Watt is defined as being equivalent to
107.5 dBSPL at around a meter from an omnidirectional source)! Of course,
most speakers are nowhere near that efficient and it can often take more than
100 electrical Watts to produce one Acoustic Watt at one meter. That would
make those speakers 1% efficient. Now, since sound pressure dissipates at a
rate inversely proportional to the distance one is from the speakers,
obviously, the larger the room, the more power it takes to maintain a
realistic sound power level in that room. After all, few people sit one meter
of less from their speakers. The point here is it's not the power itself
that's important, it's the amount of power the SPEAKERS need to reproduce the
SPL necessary to achieve the desired room loading. Some speakers can do it
with a 10 Watt SET amp and some require many hundreds of Watts for the same
effect. Now, understand, that we are talking about ONE and only one parameter
here. That's acoustical energy or volume. We aren't talking about frequency
response or imaging or any other sound characteristic. Fact is that while
Klipschorns were certainly realistically loud, they were not particularly
great sounding. They didn't have much bass below 50 Hz, and they certainly
weren't flat over the rest of the sdpectrum. I wouldn't want a pair in my
system, but at the time, when a 10 Watt amplifier was the norm, and a 25 Watt
amp was a behemoth, they produced the SPL that many audiophiles were looking
for.
> 3. WAVEFORM FIDELITY - I have been taken to task for calling it that,
> because the actual shape of a waveform is not the point, but I can't think
> of a term to describe what I mean by just simply the accuracy in the
> electronic domain of the recorded signal transmission. This includes, of
> course, frequency response, noise, and distortion. We struggled with these
> for a long time in our audio history with LP records and magnetic tape. But
> now with digital, we have essentially eliminated this characteristic from
> being a problem in recording or reproduction. Still, it is one of the
> factors that we can hear, so I list it for completeness.
designed for speakers. Hall ambience can be captured by the recording
microphones, or it can be captured by an auxiliary pair of mikes placed at
some distance in the room away from the musicians. It can also be
artificially created and added either at the recording end of the chain, or
the playback end.
> Stereo does not work like a "window into another acoustic."
setup). They're called your speakers. Their job is to recreate, as accurately
as possible, the electrical signal fed to them. Ideally, the acoustic
wavefront they produce will be exactly like the audio signal they are fed.
The problem is that's an illusive goal. It's pretty much impossible, in fact.
We can get close, and we DO get closer all the time. but each step we take
toward that goal, gets smaller than the one before it. Taken metaphorically,
we'll never get there.
Rather, if you
> think of it as a model of the original, in which your room is the performing
> space and your speaker setup attempts to get the spatial closer to the
> original, then you have a fighting chance for greater realism, but you also
> inherit the understanding that it is not an "accuracy" process, and we can
> never get all the way there. We cannot, in other words, totally get to the
> goal of a "you are there" experience but rather more like a "they are here"
> experience in which your room is the performing space and you design it for
> good sound and arrange THE BIG THREE of speaker positioning, radiation
> pattern, and room acoustics to get the model closer to the live situation.
musical ensemble is playing, how?
> So what can we hear? We can hear the spatial, spectral, and temporal
> characteristics of our listening room and speaker situation, or layout,
> superimposed on that of the recording, and we can hear the physical size,
> power, and electronic accuracy of your system. When we play back any
> recording, we CHANGE the spatial characteristics of the original to those of
> our playback system and room.
>
> That is slightly too bad, but once we understand the limitations of the
> system and what can be achieved, we can stop worrying about false goals and
> start concentrating on more fruitful paths that can lead to greater realism.
Randy Yates
May 15, 2012, 9:14:03 PM5/15/12
to
"Gary Eickmeier" <geic...@tampabay.rr.com> writes:
> [...]
stereo in the manner you're describing. The most basic linear systems
theory and acoustics will tell us this logically.
In all cases the sound reaching the listener can be described in the
frequency domain as
L(\omega)= F(\omega) . H(\omega),
where F(\omega) is the signal, H(\omega) is the room response, and "."
represents multiplication. In the time domain this is
l(t) = f(t) * h(t),
where "*" denotes convolution and h(t) is the impulse response of the
room.[1]
Consider the case of a "dead" signal source, e.g., a single human
speaker in a small room, and a "live" room in which the impulse response
h(t) is significantly longer than that of the recording environment.
Then you will necessarily perceive the "wrong" sound field.
Was Dr. Duane Cooper, formerly of the University of Illinois/Urbana a
fool? I think not! He formulated a concept of "transaural processing"
which accounted for the room response, interaural crosstalk, and head
related transfer functions so that the original auditory event could be
faithfully recreated at the listener.
The problem with Cooper's method is that, with the technology at that
time, the listener was locked into one position - not very practical.
Also the formulated problem would only work for one listener.
However, there may be feasible solutions at this day and age involving
multiple emitters, tracking technology, and adaptive beamforming. All
TBD...
--
Randy Yates
Digital Signal Labs
http://www.digitalsignallabs.com
> [...]
> The most basic and foolish mislead is thinking that good "stereo" comes from
> the direct sound alone, and trying to kill the room reflections or design a
> speaker that casts all of its sound toward your hapless ears. This
> misconception, or mislead, is caused by the confusion between stereo and
> binaural.
There are serious problems in accurately recreating a sound field using
> the direct sound alone, and trying to kill the room reflections or design a
> speaker that casts all of its sound toward your hapless ears. This
> misconception, or mislead, is caused by the confusion between stereo and
> binaural.
stereo in the manner you're describing. The most basic linear systems
theory and acoustics will tell us this logically.
In all cases the sound reaching the listener can be described in the
frequency domain as
L(\omega)= F(\omega) . H(\omega),
where F(\omega) is the signal, H(\omega) is the room response, and "."
represents multiplication. In the time domain this is
l(t) = f(t) * h(t),
where "*" denotes convolution and h(t) is the impulse response of the
room.[1]
Consider the case of a "dead" signal source, e.g., a single human
speaker in a small room, and a "live" room in which the impulse response
h(t) is significantly longer than that of the recording environment.
Then you will necessarily perceive the "wrong" sound field.
Was Dr. Duane Cooper, formerly of the University of Illinois/Urbana a
fool? I think not! He formulated a concept of "transaural processing"
which accounted for the room response, interaural crosstalk, and head
related transfer functions so that the original auditory event could be
faithfully recreated at the listener.
The problem with Cooper's method is that, with the technology at that
time, the listener was locked into one position - not very practical.
Also the formulated problem would only work for one listener.
However, there may be feasible solutions at this day and age involving
multiple emitters, tracking technology, and adaptive beamforming. All
TBD...
--
Randy Yates
Digital Signal Labs
http://www.digitalsignallabs.com
Gary Eickmeier
May 16, 2012, 6:57:25 AM5/16/12
to
Oh boy. A treasure trove of binaural vs stereo confusion.
Listen fellers, I know you probably have engineering degrees to hold over my
head, and you know calculus, and I freely admit that Audio Empire has a lot
more experience with professional recording than I do, but... well, what I
am offering as an industrial designer (those who study whole systems for
understanding before putting pencil to paper to design a particular product)
is more conceptual than all of the objections that you have stated. We all
have preconceptions about how something is, or how something should be done,
and it is hard to shake off those preconceptions, especially if you have
based a lot of your life and your career and expertise on them. Galileo and
Copernicus didn't have it easy... they all laughed at Christopher Columbus
when he said the world was round... they all laughed when Edison recorded
sound...
To try and understand the magnitude of what I perceive I am up against,
imagine duking it out with a Chistian fundamentalist over atonement
theology. He will fight you tooth and nail using the bible as his reference
and "proof."
Allow me to just re-type one small section of my paper in which I propose an
analogy that uses the "window to another acoustic" that is one of the
primary conceptions you have both used to illustrate how stereo works.
(I discuss the difference between binaural and stereophonic, the lack of a
single stereo theory or explanation of how it works, what we are doing with
the process, the Bell labs experiments, the Blumlein patent.). I continue:
The trend to note with both of these versions is that stereo is thought to
operate as a sort of windowing or portaling process wherein the sound that
was recorded is simply being relayed to the listener by the reproduction
chain. Stereophonic sound is thought to be a "trick" that attempts to fool
the ears into hearing all audible spatial properties of live sound strictly
by means of lateralization - like looking through a portal into another
acoustic space. The degree of success of the illusion is thought to depend
on the "accuracy" of the system, and the status of stereo theory as we know
it today can be thought of as a search for greater and greater accuracy.
Notice also that the above descriptions are strictly two-dimensional
processes. The theories are based only on the direct sound radiatied from a
pair or a line of speakers. They are "blind" to the effects of loudspeaker
radiation pattern, positioning, and room acoustics. We started with the
system definition as a field type system, reproduced in a real acoustic
space by loudspeakers, but as far as the explanation of how it works goes,
the playback room might as well not even exist, and nowhere do we find
reflected sound incorporated as part of stereo theory.
AN ANALOGY
The best way to illustrate this highly conceptual problem is with an
analogy.
Many people have used the "brick wall" analogy - that stereo is something
like punching out two holes in a brick wall separating you from the
performance. Some writers widen the two holes and join them together, some
claim that their systems knock down the entire wall, but we are always
witnessing teh sound through a large portal, standing on the outside looking
in.
That's a good starting point, and a nice, simple analogy to make the desired
point, but let's take it one step further. Imagine your listening room
plunked down in the middle of Symphony Hall with you in it. We're going to
punch out first two holes (or a portal) in front of us, to "let the music
in." Then, the surround sound devotees will puch out some more holes in the
rear and perhaps side walls, to let all the ambience in. Under the
"accuracy" banner, we say that when the reproduction chain gets good enough,
the sound will be indistinguishable from this punched-out shell of a room,
with nothing between you and the music but air.
The caution at this point is that this would all be very fine thinking
except that, no matter how many channels we have, we will never quite make
it all the way because, in this analogy, we must remember that the sound can
get into the imaginary room but it can't get out, and so the sound still
bounces around the listening room with the time between reflections of the
smaller space.
The main point of this section, however, is that this is NOT a good analogy
at all.
Many people, especially audiophiles, have the impression that the recording
contains a perfect image of the performance as witnessed from the best seat
in the house. This may be true with binaural, but stereophonic is a very
much different process. The problem with the above analogy is that it
pictures the sound as having been "witnessed," or recorded, from the vantage
point of the listener in the room suspended in the middle of the concert
hall. This is not the case. What we have done is dispatched the microphones
up to the orchestra, recorded the musicians and the soundstage surrounding
them, and brought back the sound to be played again from entirely within our
room, not from outside with holes punched in the walls so we can hear it.
This is quite a different thing, and it forces us for the first time to
think of the listening room not as a nuisance variable but as the performing
space itself. For better or for worse, the room must be thought of as an
integral part of the sound, to be used to construct the same sort of spatial
patterns that existed in the real concert hall, rather than fought with
sound killing materials. I believe that this is for the better, because once
we reconstruct the sound fields in the playhback room, all of the
characteristics of live sound can be present, making the sound real and not
a trick. The stereophonic recording can be thought of as a concentrate, to
be mixed with the playback acoustic in a way that models the reproduction
after the real thing. Although we must inevitably hear some of the
listeining room along with the "flavor" of the recorded acoustic, the
realism can be stunning.
Gary Eickmeier
Listen fellers, I know you probably have engineering degrees to hold over my
head, and you know calculus, and I freely admit that Audio Empire has a lot
more experience with professional recording than I do, but... well, what I
am offering as an industrial designer (those who study whole systems for
understanding before putting pencil to paper to design a particular product)
is more conceptual than all of the objections that you have stated. We all
have preconceptions about how something is, or how something should be done,
and it is hard to shake off those preconceptions, especially if you have
based a lot of your life and your career and expertise on them. Galileo and
Copernicus didn't have it easy... they all laughed at Christopher Columbus
when he said the world was round... they all laughed when Edison recorded
sound...
To try and understand the magnitude of what I perceive I am up against,
imagine duking it out with a Chistian fundamentalist over atonement
theology. He will fight you tooth and nail using the bible as his reference
and "proof."
Allow me to just re-type one small section of my paper in which I propose an
analogy that uses the "window to another acoustic" that is one of the
primary conceptions you have both used to illustrate how stereo works.
(I discuss the difference between binaural and stereophonic, the lack of a
single stereo theory or explanation of how it works, what we are doing with
the process, the Bell labs experiments, the Blumlein patent.). I continue:
The trend to note with both of these versions is that stereo is thought to
operate as a sort of windowing or portaling process wherein the sound that
was recorded is simply being relayed to the listener by the reproduction
chain. Stereophonic sound is thought to be a "trick" that attempts to fool
the ears into hearing all audible spatial properties of live sound strictly
by means of lateralization - like looking through a portal into another
acoustic space. The degree of success of the illusion is thought to depend
on the "accuracy" of the system, and the status of stereo theory as we know
it today can be thought of as a search for greater and greater accuracy.
Notice also that the above descriptions are strictly two-dimensional
processes. The theories are based only on the direct sound radiatied from a
pair or a line of speakers. They are "blind" to the effects of loudspeaker
radiation pattern, positioning, and room acoustics. We started with the
system definition as a field type system, reproduced in a real acoustic
space by loudspeakers, but as far as the explanation of how it works goes,
the playback room might as well not even exist, and nowhere do we find
reflected sound incorporated as part of stereo theory.
AN ANALOGY
The best way to illustrate this highly conceptual problem is with an
analogy.
Many people have used the "brick wall" analogy - that stereo is something
like punching out two holes in a brick wall separating you from the
performance. Some writers widen the two holes and join them together, some
claim that their systems knock down the entire wall, but we are always
witnessing teh sound through a large portal, standing on the outside looking
in.
That's a good starting point, and a nice, simple analogy to make the desired
point, but let's take it one step further. Imagine your listening room
plunked down in the middle of Symphony Hall with you in it. We're going to
punch out first two holes (or a portal) in front of us, to "let the music
in." Then, the surround sound devotees will puch out some more holes in the
rear and perhaps side walls, to let all the ambience in. Under the
"accuracy" banner, we say that when the reproduction chain gets good enough,
the sound will be indistinguishable from this punched-out shell of a room,
with nothing between you and the music but air.
The caution at this point is that this would all be very fine thinking
except that, no matter how many channels we have, we will never quite make
it all the way because, in this analogy, we must remember that the sound can
get into the imaginary room but it can't get out, and so the sound still
bounces around the listening room with the time between reflections of the
smaller space.
The main point of this section, however, is that this is NOT a good analogy
at all.
Many people, especially audiophiles, have the impression that the recording
contains a perfect image of the performance as witnessed from the best seat
in the house. This may be true with binaural, but stereophonic is a very
much different process. The problem with the above analogy is that it
pictures the sound as having been "witnessed," or recorded, from the vantage
point of the listener in the room suspended in the middle of the concert
hall. This is not the case. What we have done is dispatched the microphones
up to the orchestra, recorded the musicians and the soundstage surrounding
them, and brought back the sound to be played again from entirely within our
room, not from outside with holes punched in the walls so we can hear it.
This is quite a different thing, and it forces us for the first time to
think of the listening room not as a nuisance variable but as the performing
space itself. For better or for worse, the room must be thought of as an
integral part of the sound, to be used to construct the same sort of spatial
patterns that existed in the real concert hall, rather than fought with
sound killing materials. I believe that this is for the better, because once
we reconstruct the sound fields in the playhback room, all of the
characteristics of live sound can be present, making the sound real and not
a trick. The stereophonic recording can be thought of as a concentrate, to
be mixed with the playback acoustic in a way that models the reproduction
after the real thing. Although we must inevitably hear some of the
listeining room along with the "flavor" of the recorded acoustic, the
realism can be stunning.
Gary Eickmeier
Gary Eickmeier
May 16, 2012, 6:57:43 AM5/16/12
to
{Moderators - please allow edit}
Oh boy. This is what I was afraed of.
Listen fellers, I know you probably have engineering degrees to hold over my
head, and you know calculus, and I freely admit that Audio Empire has a lot
more experience with professional recording than I do, but... well, what I
am offering as an industrial designer (those who study whole systems for
understanding before putting pencil to paper to design a particular product)
is more conceptual than all of the objections that you have stated. We all
have preconceptions about how something is, or how something should be done,
and it is hard to shake off those preconceptions, especially if you have
based a lot of your life and your career and expertise on them. Galileo and
Copernicus didn't have it easy... they all laughed at Christopher Columbus
when he said the world was round... they all laughed when Edison recorded
sound...
Oh boy. This is what I was afraed of.
Listen fellers, I know you probably have engineering degrees to hold over my
head, and you know calculus, and I freely admit that Audio Empire has a lot
more experience with professional recording than I do, but... well, what I
am offering as an industrial designer (those who study whole systems for
understanding before putting pencil to paper to design a particular product)
is more conceptual than all of the objections that you have stated. We all
have preconceptions about how something is, or how something should be done,
and it is hard to shake off those preconceptions, especially if you have
based a lot of your life and your career and expertise on them. Galileo and
Copernicus didn't have it easy... they all laughed at Christopher Columbus
when he said the world was round... they all laughed when Edison recorded
sound...
Andrew Haley
May 16, 2012, 11:27:38 AM5/16/12
to
Audio Empire <audio_...@comcast.net> wrote:
> The Klipshorns were 50% efficient. That meant that every two Watts
> of amplifier power produced one acoustic Watt of sound (One acoustic
> Watt is defined as being equivalent to 107.5 dBSPL at around a meter
> from an omnidirectional source)!
Even if that famous 104 dB/W figure is true, AFAICR that's a half-
> The Klipshorns were 50% efficient. That meant that every two Watts
> of amplifier power produced one acoustic Watt of sound (One acoustic
> Watt is defined as being equivalent to 107.5 dBSPL at around a meter
> from an omnidirectional source)!
space measurement, and the horns are highly directional. It doesn't
equate to 50% efficiency, which would be miraculous. I reckon it's
about 15% efficiency, which is extremely good.
> Of course, most speakers are nowhere near that efficient and it can
> often take more than 100 electrical Watts to produce one Acoustic
> Watt at one meter. That would make those speakers 1% efficient. Now,
> since sound pressure dissipates at a rate inversely proportional to
> the distance one is from the speakers,
Andrew.
Audio Empire
May 16, 2012, 7:34:25 PM5/16/12
to
On Wed, 16 May 2012 03:57:25 -0700, Gary Eickmeier wrote
(in article <a1hfgl...@mid.individual.net>):
> Oh boy. A treasure trove of binaural vs stereo confusion.
>
> Listen fellers, I know you probably have engineering degrees to hold over my
> head, and you know calculus, and I freely admit that Audio Empire has a lot
> more experience with professional recording than I do, but... well, what I
> am offering as an industrial designer (those who study whole systems for
> understanding before putting pencil to paper to design a particular product)
> is more conceptual than all of the objections that you have stated. We all
> have preconceptions about how something is, or how something should be done,
> and it is hard to shake off those preconceptions, especially if you have
> based a lot of your life and your career and expertise on them. Galileo and
> Copernicus didn't have it easy... they all laughed at Christopher Columbus
> when he said the world was round... they all laughed when Edison recorded
> sound...
>
> To try and understand the magnitude of what I perceive I am up against,
> imagine duking it out with a Chistian fundamentalist over atonement
> theology. He will fight you tooth and nail using the bible as his reference
> and "proof."
I don't think that's really an apt analogy. You have formulated, in a vacuum
of actual knowledge, and experience, it seems, a bunch of notions about how
you think this stuff works. People with knowledge (those engineering degrees
that you mention) and actual experience with the concepts that you blithely
throw around, try to explain to you why your notions are based on assumptions
not in evidence. It's not a "fight" between fundamentalism against atonement
theology, it's a fight between how you want things to be and how they
actually are. It's like someone with a deep background in physics and
electronics arguing with a layman who is convinced that he can hear the
difference between different expensive audio cables. The scientist KNOWS that
the cables can't sound any different, and can explain to the "true believer"
why this HAS to be so, but the true believer hasn't the background to follow
the argument and KNOWS what he thinks he hears.
the sound source, it is overly simplistic. Too simplistic to explain the
signal that the speakers are reproducing. For instance, windows will never
give the listener inside the room, any image specificity, any front-to-back
layering, or any image height. That;s because speakers are attempting to
reproduce an audio signal picked up by microphones with certain
characteristics that are very unlike "two open windows".
field as produced by the speakers. It is not, by any stretch of the
imagination, a "model" for stereophonic sound and it would be a mistake to
see it that way.
(in article <a1hfgl...@mid.individual.net>):
> Oh boy. A treasure trove of binaural vs stereo confusion.
>
> Listen fellers, I know you probably have engineering degrees to hold over my
> head, and you know calculus, and I freely admit that Audio Empire has a lot
> more experience with professional recording than I do, but... well, what I
> am offering as an industrial designer (those who study whole systems for
> understanding before putting pencil to paper to design a particular product)
> is more conceptual than all of the objections that you have stated. We all
> have preconceptions about how something is, or how something should be done,
> and it is hard to shake off those preconceptions, especially if you have
> based a lot of your life and your career and expertise on them. Galileo and
> Copernicus didn't have it easy... they all laughed at Christopher Columbus
> when he said the world was round... they all laughed when Edison recorded
> sound...
>
> To try and understand the magnitude of what I perceive I am up against,
> imagine duking it out with a Chistian fundamentalist over atonement
> theology. He will fight you tooth and nail using the bible as his reference
> and "proof."
of actual knowledge, and experience, it seems, a bunch of notions about how
you think this stuff works. People with knowledge (those engineering degrees
that you mention) and actual experience with the concepts that you blithely
throw around, try to explain to you why your notions are based on assumptions
not in evidence. It's not a "fight" between fundamentalism against atonement
theology, it's a fight between how you want things to be and how they
actually are. It's like someone with a deep background in physics and
electronics arguing with a layman who is convinced that he can hear the
difference between different expensive audio cables. The scientist KNOWS that
the cables can't sound any different, and can explain to the "true believer"
why this HAS to be so, but the true believer hasn't the background to follow
the argument and KNOWS what he thinks he hears.
>
> Allow me to just re-type one small section of my paper in which I propose an
> analogy that uses the "window to another acoustic" that is one of the
> primary conceptions you have both used to illustrate how stereo works.
>
> (I discuss the difference between binaural and stereophonic, the lack of a
> single stereo theory or explanation of how it works, what we are doing with
> the process, the Bell labs experiments, the Blumlein patent.). I continue:
>
>
>
> The trend to note with both of these versions is that stereo is thought to
> operate as a sort of windowing or portaling process wherein the sound that
> was recorded is simply being relayed to the listener by the reproduction
> chain. Stereophonic sound is thought to be a "trick" that attempts to fool
> the ears into hearing all audible spatial properties of live sound strictly
> by means of lateralization - like looking through a portal into another
> acoustic space. The degree of success of the illusion is thought to depend
> on the "accuracy" of the system, and the status of stereo theory as we know
> it today can be thought of as a search for greater and greater accuracy.
>
> Notice also that the above descriptions are strictly two-dimensional
> processes. The theories are based only on the direct sound radiatied from a
> pair or a line of speakers. They are "blind" to the effects of loudspeaker
> radiation pattern, positioning, and room acoustics. We started with the
> system definition as a field type system, reproduced in a real acoustic
> space by loudspeakers, but as far as the explanation of how it works goes,
> the playback room might as well not even exist, and nowhere do we find
> reflected sound incorporated as part of stereo theory.
Well the window analogy is useful to explain the listener's relationship to
> Allow me to just re-type one small section of my paper in which I propose an
> analogy that uses the "window to another acoustic" that is one of the
> primary conceptions you have both used to illustrate how stereo works.
>
> (I discuss the difference between binaural and stereophonic, the lack of a
> single stereo theory or explanation of how it works, what we are doing with
> the process, the Bell labs experiments, the Blumlein patent.). I continue:
>
>
>
> The trend to note with both of these versions is that stereo is thought to
> operate as a sort of windowing or portaling process wherein the sound that
> was recorded is simply being relayed to the listener by the reproduction
> chain. Stereophonic sound is thought to be a "trick" that attempts to fool
> the ears into hearing all audible spatial properties of live sound strictly
> by means of lateralization - like looking through a portal into another
> acoustic space. The degree of success of the illusion is thought to depend
> on the "accuracy" of the system, and the status of stereo theory as we know
> it today can be thought of as a search for greater and greater accuracy.
>
> Notice also that the above descriptions are strictly two-dimensional
> processes. The theories are based only on the direct sound radiatied from a
> pair or a line of speakers. They are "blind" to the effects of loudspeaker
> radiation pattern, positioning, and room acoustics. We started with the
> system definition as a field type system, reproduced in a real acoustic
> space by loudspeakers, but as far as the explanation of how it works goes,
> the playback room might as well not even exist, and nowhere do we find
> reflected sound incorporated as part of stereo theory.
the sound source, it is overly simplistic. Too simplistic to explain the
signal that the speakers are reproducing. For instance, windows will never
give the listener inside the room, any image specificity, any front-to-back
layering, or any image height. That;s because speakers are attempting to
reproduce an audio signal picked up by microphones with certain
characteristics that are very unlike "two open windows".
>
> AN ANALOGY
>
> The best way to illustrate this highly conceptual problem is with an
> analogy.
>
> Many people have used the "brick wall" analogy - that stereo is something
> like punching out two holes in a brick wall separating you from the
> performance.
Only in the sense that it explains the listener's RELATIONSHIP with the sound
> AN ANALOGY
>
> The best way to illustrate this highly conceptual problem is with an
> analogy.
>
> Many people have used the "brick wall" analogy - that stereo is something
> like punching out two holes in a brick wall separating you from the
> performance.
field as produced by the speakers. It is not, by any stretch of the
imagination, a "model" for stereophonic sound and it would be a mistake to
see it that way.
Gary Eickmeier
May 16, 2012, 7:41:19 PM5/16/12
to
"Audio Empire" <audio_...@comcast.net> wrote in message
news:joupu...@news4.newsguy.com...
> The human ear is a sensitive tool, no doubt about it. Unfortunately, it is
> also an interpretive tool. There is no sound preception without the brain
> and
> the brain brings with it a lifetime of experience, preconceptions, and
> personal preferences. It applies these factors to everything we hear and
> they're difficult to overcome. In fact, I'd go so far as to say that we,
> as
> individuals, can't overcome them. We are going to hear what we want to
> hear
> or what we expect to hear. The only way around this is to take human bias
> out
> of the equation with tests that are either totally objective (such as
> measurements using instrumentation) or by taking part in listening tests
> which remove as much of the human propensity for self-delusion as possible
> and relying on the statistical results. To paraphrase an old adage: he who
> trusts his own ear/brain interface to judge audio qualities is a fool.
Careful. Our ears are the final arbiter in audibility of effects. You just
have to keep the brain at by with DBT. What I mean by hard-nosed listening
is trying to keep the overactive imagination out of the discussion and being
honest about what you are hearing. If you can tell that the sound is coming
from a pair of speakers, and you are not being fooled into thinking "you are
there," then admit it and try for some improvements.
> Phase anomalies are real. You can measure them and you can easily hear
> their
> effects. All one has to do is walk past a stereo pair of speakers that are
> wired out-of phase to instantly hear the results. You can also take a
> recording made with a pair of spaced omnis and sum the two channels to
> mono
> to immediately hear (and see, on an oscilloscope) some of the instruments
> go
> away.
>
Monophonic phase response is not audible, and wasting time time aligning
drivers is a dead end.
> I have to disagree here. While you are correct about being able to tell,
> even
> blindfolded, the approximate size of a room you're in, you are wrong about
> the results. It is possible to make a small room sound good much more
> easily
> than it is possible to make a large room sound good. Small rooms have all
> the
> characteristics that you mention (and then some) but they are all fairly
> controllable.
Would you agree that you cannot make a room sound bigger than it actually is
by playing a sound recorded in a larger room?
> Again you are grossly oversimplifying. Power, in and of itself is merely a
> means to an end. The end is moving air. The more air you can move the more
> realistically an audio system will load the room with sound and the amount
> of
> air any speaker can move with a Watt of electrical power from an amplifier
> is
> determined by two things: the efficiency of the speaker and the volume of
> the
> space one is trying to fill.
and so on. Obviously, all I mean is acoustic power. I don't care how you get
there, with normal speakers and a lot of power, or efficient horn speakers
and less powerful amps, just mean how loud can it go undistorted.
.
> Actually, it is a pair of windows (in a traditional two-channel stereo
> setup). They're called your speakers. Their job is to recreate, as
> accurately
> as possible, the electrical signal fed to them. Ideally, the acoustic
> wavefront they produce will be exactly like the audio signal they are fed.
> The problem is that's an illusive goal. It's pretty much impossible, in
> fact.
> We can get close, and we DO get closer all the time. but each step we take
> toward that goal, gets smaller than the one before it. Taken
> metaphorically,
> we'll never get there.
Good illustration of a false goal. Accuracy of what compared to what? Your
statement above would indicate that you think the ideal speaker is a point
source directional jobby that has no output to the rear or sides anc can
cast all of its output directly toward your ears. That would be perfect
"accuracy" of the wavefront compared to the electrical signal fed them
But stereo is not an "accuracy" process. That signal contains recorded
information from the venue that arrived at the microphones from widely
varying incident angles. I think you know what I mean. To shove all of that
recorded sound at you from just that one point in space would CHANGE the
spatial characteristics of the original to those of your speakers. So would
that be "accurate"?
>
>> So what can we hear? We can hear the spatial, spectral, and temporal
>> characteristics of our listening room and speaker situation, or layout,
>> superimposed on that of the recording, and we can hear the physical size,
>> power, and electronic accuracy of your system. When we play back any
>> recording, we CHANGE the spatial characteristics of the original to those
>> of
>> our playback system and room.
>>
>> That is slightly too bad, but once we understand the limitations of the
>> system and what can be achieved, we can stop worrying about false goals
>> and
>> start concentrating on more fruitful paths that can lead to greater
>> realism.
>
> Which would be?
Getting the spatial more correct by looking at the reproduction as a model
of the live situation, rather than a "window" to another space. This, in
turn, forces you to think about "the big three" of radiation pattern, room
positioning, and room acoustics.
Gary Eickmeier
news:joupu...@news4.newsguy.com...
> The human ear is a sensitive tool, no doubt about it. Unfortunately, it is
> also an interpretive tool. There is no sound preception without the brain
> and
> the brain brings with it a lifetime of experience, preconceptions, and
> personal preferences. It applies these factors to everything we hear and
> they're difficult to overcome. In fact, I'd go so far as to say that we,
> as
> individuals, can't overcome them. We are going to hear what we want to
> hear
> or what we expect to hear. The only way around this is to take human bias
> out
> of the equation with tests that are either totally objective (such as
> measurements using instrumentation) or by taking part in listening tests
> which remove as much of the human propensity for self-delusion as possible
> and relying on the statistical results. To paraphrase an old adage: he who
> trusts his own ear/brain interface to judge audio qualities is a fool.
have to keep the brain at by with DBT. What I mean by hard-nosed listening
is trying to keep the overactive imagination out of the discussion and being
honest about what you are hearing. If you can tell that the sound is coming
from a pair of speakers, and you are not being fooled into thinking "you are
there," then admit it and try for some improvements.
> Phase anomalies are real. You can measure them and you can easily hear
> their
> effects. All one has to do is walk past a stereo pair of speakers that are
> wired out-of phase to instantly hear the results. You can also take a
> recording made with a pair of spaced omnis and sum the two channels to
> mono
> to immediately hear (and see, on an oscilloscope) some of the instruments
> go
> away.
>
drivers is a dead end.
> I have to disagree here. While you are correct about being able to tell,
> even
> blindfolded, the approximate size of a room you're in, you are wrong about
> the results. It is possible to make a small room sound good much more
> easily
> than it is possible to make a large room sound good. Small rooms have all
> the
> characteristics that you mention (and then some) but they are all fairly
> controllable.
by playing a sound recorded in a larger room?
> Again you are grossly oversimplifying. Power, in and of itself is merely a
> means to an end. The end is moving air. The more air you can move the more
> realistically an audio system will load the room with sound and the amount
> of
> air any speaker can move with a Watt of electrical power from an amplifier
> is
> determined by two things: the efficiency of the speaker and the volume of
> the
> space one is trying to fill.
there, with normal speakers and a lot of power, or efficient horn speakers
and less powerful amps, just mean how loud can it go undistorted.
.
> Actually, it is a pair of windows (in a traditional two-channel stereo
> setup). They're called your speakers. Their job is to recreate, as
> accurately
> as possible, the electrical signal fed to them. Ideally, the acoustic
> wavefront they produce will be exactly like the audio signal they are fed.
> The problem is that's an illusive goal. It's pretty much impossible, in
> fact.
> We can get close, and we DO get closer all the time. but each step we take
> toward that goal, gets smaller than the one before it. Taken
> metaphorically,
> we'll never get there.
statement above would indicate that you think the ideal speaker is a point
source directional jobby that has no output to the rear or sides anc can
cast all of its output directly toward your ears. That would be perfect
"accuracy" of the wavefront compared to the electrical signal fed them
But stereo is not an "accuracy" process. That signal contains recorded
information from the venue that arrived at the microphones from widely
varying incident angles. I think you know what I mean. To shove all of that
recorded sound at you from just that one point in space would CHANGE the
spatial characteristics of the original to those of your speakers. So would
that be "accurate"?
>
>
> Rather, if you
>> think of it as a model of the original, in which your room is the
>> performing
>> space and your speaker setup attempts to get the spatial closer to the
>> original, then you have a fighting chance for greater realism, but you
>> also
>> inherit the understanding that it is not an "accuracy" process, and we
>> can
>> never get all the way there. We cannot, in other words, totally get to
>> the
>> goal of a "you are there" experience but rather more like a "they are
>> here"
>> experience in which your room is the performing space and you design it
>> for
>> good sound and arrange THE BIG THREE of speaker positioning, radiation
>> pattern, and room acoustics to get the model closer to the live
>> situation.
>
> And this would be different from two open windows onto a space where a
> musical ensemble is playing, how?
Please see the next thread, "What Can We Hear?".
>
> Rather, if you
>> think of it as a model of the original, in which your room is the
>> performing
>> space and your speaker setup attempts to get the spatial closer to the
>> original, then you have a fighting chance for greater realism, but you
>> also
>> inherit the understanding that it is not an "accuracy" process, and we
>> can
>> never get all the way there. We cannot, in other words, totally get to
>> the
>> goal of a "you are there" experience but rather more like a "they are
>> here"
>> experience in which your room is the performing space and you design it
>> for
>> good sound and arrange THE BIG THREE of speaker positioning, radiation
>> pattern, and room acoustics to get the model closer to the live
>> situation.
>
> And this would be different from two open windows onto a space where a
> musical ensemble is playing, how?
>
>> So what can we hear? We can hear the spatial, spectral, and temporal
>> characteristics of our listening room and speaker situation, or layout,
>> superimposed on that of the recording, and we can hear the physical size,
>> power, and electronic accuracy of your system. When we play back any
>> recording, we CHANGE the spatial characteristics of the original to those
>> of
>> our playback system and room.
>>
>> That is slightly too bad, but once we understand the limitations of the
>> system and what can be achieved, we can stop worrying about false goals
>> and
>> start concentrating on more fruitful paths that can lead to greater
>> realism.
>
> Which would be?
of the live situation, rather than a "window" to another space. This, in
turn, forces you to think about "the big three" of radiation pattern, room
positioning, and room acoustics.
Gary Eickmeier
Audio Empire
May 16, 2012, 10:59:37 PM5/16/12
to
On Wed, 16 May 2012 16:41:19 -0700, Gary Eickmeier wrote
(in article <a1is8u...@mid.individual.net>):
> "Audio Empire" <audio_...@comcast.net> wrote in message
> news:joupu...@news4.newsguy.com...
>
>
>> The human ear is a sensitive tool, no doubt about it. Unfortunately, it is
>> also an interpretive tool. There is no sound preception without the brain
>> and
>> the brain brings with it a lifetime of experience, preconceptions, and
>> personal preferences. It applies these factors to everything we hear and
>> they're difficult to overcome. In fact, I'd go so far as to say that we,
>> as
>> individuals, can't overcome them. We are going to hear what we want to
>> hear
>> or what we expect to hear. The only way around this is to take human bias
>> out
>> of the equation with tests that are either totally objective (such as
>> measurements using instrumentation) or by taking part in listening tests
>> which remove as much of the human propensity for self-delusion as possible
>> and relying on the statistical results. To paraphrase an old adage: he who
>> trusts his own ear/brain interface to judge audio qualities is a fool.
>
> Careful. Our ears are the final arbiter in audibility of effects. You just
> have to keep the brain at by with DBT. What I mean by hard-nosed listening
> is trying to keep the overactive imagination out of the discussion and being
> honest about what you are hearing. If you can tell that the sound is coming
> from a pair of speakers, and you are not being fooled into thinking "you are
> there," then admit it and try for some improvements.
I think I just said that...
>> Phase anomalies are real. You can measure them and you can easily hear
>> their
>> effects. All one has to do is walk past a stereo pair of speakers that are
>> wired out-of phase to instantly hear the results. You can also take a
>> recording made with a pair of spaced omnis and sum the two channels to
>> mono
>> to immediately hear (and see, on an oscilloscope) some of the instruments
>> go
>> away.
>>
>
> Monophonic phase response is not audible, and wasting time time aligning
> drivers is a dead end.
That's irrelevant to my comments. In stereo, phase differences are part of
what constitutes "channel separation" and therefore imaging. Also, there is
nothing of a "waste of time" about making sure all of your speakers are
in-phase and it's easy to hear when they are not. Yet, if I had a dollar for
every stereo store's demo room I've entered only to say to the salesperson
"Your speakers are out of phase", I could have a really good steak dinner at
Ruth's Chris!
Also, the fact that spaced omni's aren't phase coherent is one of the reasons
why Telarc's classical recordings never imaged as well as they should. I'd
say phase is very important. OTOH, I've never heard any REAL advantage to
"time aligned" drivers in speakers. It might be theoretically important, but
the difference certainly doesn't reach out and grab you.
>
>> I have to disagree here. While you are correct about being able to tell,
>> even
>> blindfolded, the approximate size of a room you're in, you are wrong about
>> the results. It is possible to make a small room sound good much more
>> easily
>> than it is possible to make a large room sound good. Small rooms have all
>> the
>> characteristics that you mention (and then some) but they are all fairly
>> controllable.
>
> Would you agree that you cannot make a room sound bigger than it actually is
> by playing a sound recorded in a larger room?
Of course you can't. However, you can use a DSP based playback reverb system
(such as those made by Lexicon) and speakers placed in the back of a smallish
room and by choosing the correct amounts of delay and reverb make the room
sound bigger. Like I said, a small room's anomalies are controllable by
various means.
>> Again you are grossly oversimplifying. Power, in and of itself is merely a
>> means to an end. The end is moving air. The more air you can move the more
>> realistically an audio system will load the room with sound and the amount
>> of
>> air any speaker can move with a Watt of electrical power from an amplifier
>> is
>> determined by two things: the efficiency of the speaker and the volume of
>> the
>> space one is trying to fill.
>
> and so on. Obviously, all I mean is acoustic power. I don't care how you get
> there, with normal speakers and a lot of power, or efficient horn speakers
> and less powerful amps, just mean how loud can it go undistorted.
Then you should have said acoustic power. As you wrote it, it pertained to
amplifier power. That's all I had to go by in my response.
>> Actually, it is a pair of windows (in a traditional two-channel stereo
>> setup). They're called your speakers. Their job is to recreate, as
>> accurately
>> as possible, the electrical signal fed to them. Ideally, the acoustic
>> wavefront they produce will be exactly like the audio signal they are fed.
>> The problem is that's an illusive goal. It's pretty much impossible, in
>> fact.
>> We can get close, and we DO get closer all the time. but each step we take
>> toward that goal, gets smaller than the one before it. Taken
>> metaphorically,
>> we'll never get there.
>
> Good illustration of a false goal. Accuracy of what compared to what?
That should be apparent. The speakers can only be accurate to what's fed them
and that's all I meant. The acoustic waveform emanating from the speakers
should look EXACTLY like the electrical signal fed to it. I.E. feed the
speakers a perfect square wave and it should produce a perfect square wave in
space - at any frequency in the audio spectrum. No overshoots, no rounding of
the flat tops of waves, no ringing. Obviously, that's impossible.
Your
> statement above would indicate that you think the ideal speaker is a point
> source directional jobby that has no output to the rear or sides anc can
> cast all of its output directly toward your ears. That would be perfect
> "accuracy" of the wavefront compared to the electrical signal fed them
I don't think that's obvious at all, and in fact, I said nothing of the sort!
The perfect speaker is, by definition, an infinitely small, omnidirectional
point source in the form of a pulsating sphere that can respond instantly to
every nuance of the signal fed to it (see above).
physics of reality mitigate against it. But trying to get there (such as what
MBL is trying to do with the MB-101 MkII and their pulsating spheres) is a
worthy goal.
OK first of all, are you aware that at least 90% of all of the commercially
available classical recordings don't image anywhere near as well as the state
of the art has allowed since stereo recording began in the mid-Fifties? How
can you "get the spatial more correct" on the listening end when most record
companies can't get it right on the recording end, the end over which you and
I, as listeners have NO control?
And getting our system to be more like a model of the live situation can't be
done with two channels, but I'll let you in on something, you can get damn
close. I have symphony orchestra recordings that I have made with just two
cardioid condenser microphones mounted on a stereo "T"-bar with their axis's
90-degrees apart that image so well, that you can close your eyes and point
to every instrument in the orchestra. You can even tell that the back row of
brass is sitting up on risers and are higher than the woodwinds in front of
them! How's that for realistic soundstage. It can be done, it has been done
in commercial recordings, but it's SELDOM done. I can count on the fingers of
two hands the commercial classical recordings that I have (and I have
literally thousands both in Vinyl and CD) that image like that. You want to
go on a crusade for better sound? Start there.
(in article <a1is8u...@mid.individual.net>):
> "Audio Empire" <audio_...@comcast.net> wrote in message
> news:joupu...@news4.newsguy.com...
>
>
>> The human ear is a sensitive tool, no doubt about it. Unfortunately, it is
>> also an interpretive tool. There is no sound preception without the brain
>> and
>> the brain brings with it a lifetime of experience, preconceptions, and
>> personal preferences. It applies these factors to everything we hear and
>> they're difficult to overcome. In fact, I'd go so far as to say that we,
>> as
>> individuals, can't overcome them. We are going to hear what we want to
>> hear
>> or what we expect to hear. The only way around this is to take human bias
>> out
>> of the equation with tests that are either totally objective (such as
>> measurements using instrumentation) or by taking part in listening tests
>> which remove as much of the human propensity for self-delusion as possible
>> and relying on the statistical results. To paraphrase an old adage: he who
>> trusts his own ear/brain interface to judge audio qualities is a fool.
>
> Careful. Our ears are the final arbiter in audibility of effects. You just
> have to keep the brain at by with DBT. What I mean by hard-nosed listening
> is trying to keep the overactive imagination out of the discussion and being
> honest about what you are hearing. If you can tell that the sound is coming
> from a pair of speakers, and you are not being fooled into thinking "you are
> there," then admit it and try for some improvements.
>> Phase anomalies are real. You can measure them and you can easily hear
>> their
>> effects. All one has to do is walk past a stereo pair of speakers that are
>> wired out-of phase to instantly hear the results. You can also take a
>> recording made with a pair of spaced omnis and sum the two channels to
>> mono
>> to immediately hear (and see, on an oscilloscope) some of the instruments
>> go
>> away.
>>
>
> Monophonic phase response is not audible, and wasting time time aligning
> drivers is a dead end.
what constitutes "channel separation" and therefore imaging. Also, there is
nothing of a "waste of time" about making sure all of your speakers are
in-phase and it's easy to hear when they are not. Yet, if I had a dollar for
every stereo store's demo room I've entered only to say to the salesperson
"Your speakers are out of phase", I could have a really good steak dinner at
Ruth's Chris!
Also, the fact that spaced omni's aren't phase coherent is one of the reasons
why Telarc's classical recordings never imaged as well as they should. I'd
say phase is very important. OTOH, I've never heard any REAL advantage to
"time aligned" drivers in speakers. It might be theoretically important, but
the difference certainly doesn't reach out and grab you.
>
>> I have to disagree here. While you are correct about being able to tell,
>> even
>> blindfolded, the approximate size of a room you're in, you are wrong about
>> the results. It is possible to make a small room sound good much more
>> easily
>> than it is possible to make a large room sound good. Small rooms have all
>> the
>> characteristics that you mention (and then some) but they are all fairly
>> controllable.
>
> Would you agree that you cannot make a room sound bigger than it actually is
> by playing a sound recorded in a larger room?
(such as those made by Lexicon) and speakers placed in the back of a smallish
room and by choosing the correct amounts of delay and reverb make the room
sound bigger. Like I said, a small room's anomalies are controllable by
various means.
>> Again you are grossly oversimplifying. Power, in and of itself is merely a
>> means to an end. The end is moving air. The more air you can move the more
>> realistically an audio system will load the room with sound and the amount
>> of
>> air any speaker can move with a Watt of electrical power from an amplifier
>> is
>> determined by two things: the efficiency of the speaker and the volume of
>> the
>> space one is trying to fill.
>
> and so on. Obviously, all I mean is acoustic power. I don't care how you get
> there, with normal speakers and a lot of power, or efficient horn speakers
> and less powerful amps, just mean how loud can it go undistorted.
amplifier power. That's all I had to go by in my response.
>> Actually, it is a pair of windows (in a traditional two-channel stereo
>> setup). They're called your speakers. Their job is to recreate, as
>> accurately
>> as possible, the electrical signal fed to them. Ideally, the acoustic
>> wavefront they produce will be exactly like the audio signal they are fed.
>> The problem is that's an illusive goal. It's pretty much impossible, in
>> fact.
>> We can get close, and we DO get closer all the time. but each step we take
>> toward that goal, gets smaller than the one before it. Taken
>> metaphorically,
>> we'll never get there.
>
> Good illustration of a false goal. Accuracy of what compared to what?
and that's all I meant. The acoustic waveform emanating from the speakers
should look EXACTLY like the electrical signal fed to it. I.E. feed the
speakers a perfect square wave and it should produce a perfect square wave in
space - at any frequency in the audio spectrum. No overshoots, no rounding of
the flat tops of waves, no ringing. Obviously, that's impossible.
Your
> statement above would indicate that you think the ideal speaker is a point
> source directional jobby that has no output to the rear or sides anc can
> cast all of its output directly toward your ears. That would be perfect
> "accuracy" of the wavefront compared to the electrical signal fed them
The perfect speaker is, by definition, an infinitely small, omnidirectional
point source in the form of a pulsating sphere that can respond instantly to
every nuance of the signal fed to it (see above).
>
> But stereo is not an "accuracy" process. That signal contains recorded
> information from the venue that arrived at the microphones from widely
> varying incident angles. I think you know what I mean. To shove all of that
> recorded sound at you from just that one point in space would CHANGE the
> spatial characteristics of the original to those of your speakers. So would
> that be "accurate"?
Accuracy on that level is a goal. It is not an achievable goal, because the
> But stereo is not an "accuracy" process. That signal contains recorded
> information from the venue that arrived at the microphones from widely
> varying incident angles. I think you know what I mean. To shove all of that
> recorded sound at you from just that one point in space would CHANGE the
> spatial characteristics of the original to those of your speakers. So would
> that be "accurate"?
physics of reality mitigate against it. But trying to get there (such as what
MBL is trying to do with the MB-101 MkII and their pulsating spheres) is a
worthy goal.
available classical recordings don't image anywhere near as well as the state
of the art has allowed since stereo recording began in the mid-Fifties? How
can you "get the spatial more correct" on the listening end when most record
companies can't get it right on the recording end, the end over which you and
I, as listeners have NO control?
And getting our system to be more like a model of the live situation can't be
done with two channels, but I'll let you in on something, you can get damn
close. I have symphony orchestra recordings that I have made with just two
cardioid condenser microphones mounted on a stereo "T"-bar with their axis's
90-degrees apart that image so well, that you can close your eyes and point
to every instrument in the orchestra. You can even tell that the back row of
brass is sitting up on risers and are higher than the woodwinds in front of
them! How's that for realistic soundstage. It can be done, it has been done
in commercial recordings, but it's SELDOM done. I can count on the fingers of
two hands the commercial classical recordings that I have (and I have
literally thousands both in Vinyl and CD) that image like that. You want to
go on a crusade for better sound? Start there.
Gary Eickmeier
May 17, 2012, 6:48:17 AM5/17/12
to
"Audio Empire" <audio_...@comcast.net> wrote in message
news:jp1di...@news6.newsguy.com...
analogy, and you didn't follow it. It is not a fight between fundamentalists
and atonement theology; it is the fundamentalists who believe in atonement
theology. They support it as "experts" because of all they have learned from
the bible and bible school. But if you come along and try to tell them that
these notions are wrong, they will give all of the arguments that you have
just given me, that what I am saying is not supported by the "bible" of the
Handbook of Audio Engineering.
I have tried to point out that even among the "experts" there is no single
stereo theory, all laid out and accepted by all engineers. There is just
about as much variability in the audio engineering community as there is in
religion. Look at loudspeaker design man. No one knows what the hell he is
doing. There are dipoles, bipoles, omnis, and megaphones, line sources,
point sources, wallspeakers and free standing speakers. No one has a clue
how or why to do any of this, nor is there a guideline for any sort of
"correct" design or theory of stereo.
Nor am I just entering the room. I have been studying this stuff for almost
30 years now.
>> AN ANALOGY
>>
>> The best way to illustrate this highly conceptual problem is with an
>> analogy.
>>
>> Many people have used the "brick wall" analogy - that stereo is something
>> like punching out two holes in a brick wall separating you from the
>> performance.
>
> Only in the sense that it explains the listener's RELATIONSHIP with the
> sound
> field as produced by the speakers. It is not, by any stretch of the
> imagination, a "model" for stereophonic sound and it would be a mistake to
> see it that way.
Gary Eickmeier
ScottW
May 17, 2012, 12:05:38 PM5/17/12
to
On May 17, 3:48 am, "Gary Eickmeier" <geick...@tampabay.rr.com> wrote:
> "Audio Empire" <audio_emp...@comcast.net> wrote in message
already has).
Speaker design is a series of compromises and each design path has a
different set. Many of these are to address characteristics of
different rooms and/or listener preference.
I would agree that the choice of compromise is worthy of debate. I'm
not sure I would agree that the "perfect speaker" is omnidirectional
given the objective is to recreate a sound of an event in one location
in a completely different (acoustically) location.
ScottW
> "Audio Empire" <audio_emp...@comcast.net> wrote in message
>
> OK, I tried to edit that paragraph, but I really did think it an apt
> analogy, and you didn't follow it. It is not a fight between fundamentalists
> and atonement theology; it is the fundamentalists who believe in atonement
> theology. They support it as "experts" because of all they have learned from
> the bible and bible school. But if you come along and try to tell them that
> these notions are wrong, they will give all of the arguments that you have
> just given me, that what I am saying is not supported by the "bible" of the
> Handbook of Audio Engineering.
>
> I have tried to point out that even among the "experts" there is no single
> stereo theory, all laid out and accepted by all engineers. There is just
> about as much variability in the audio engineering community as there is in
> religion. Look at loudspeaker design man. No one knows what the hell he is
> doing. There are dipoles, bipoles, omnis, and megaphones, line sources,
> point sources, wallspeakers and free standing speakers. No one has a clue
> how or why to do any of this, nor is there a guideline for any sort of
> "correct" design or theory of stereo.
The conversation is going to break down into hyperbole (or perhaps
> OK, I tried to edit that paragraph, but I really did think it an apt
> analogy, and you didn't follow it. It is not a fight between fundamentalists
> and atonement theology; it is the fundamentalists who believe in atonement
> theology. They support it as "experts" because of all they have learned from
> the bible and bible school. But if you come along and try to tell them that
> these notions are wrong, they will give all of the arguments that you have
> just given me, that what I am saying is not supported by the "bible" of the
> Handbook of Audio Engineering.
>
> I have tried to point out that even among the "experts" there is no single
> stereo theory, all laid out and accepted by all engineers. There is just
> about as much variability in the audio engineering community as there is in
> religion. Look at loudspeaker design man. No one knows what the hell he is
> doing. There are dipoles, bipoles, omnis, and megaphones, line sources,
> point sources, wallspeakers and free standing speakers. No one has a clue
> how or why to do any of this, nor is there a guideline for any sort of
> "correct" design or theory of stereo.
already has).
Speaker design is a series of compromises and each design path has a
different set. Many of these are to address characteristics of
different rooms and/or listener preference.
I would agree that the choice of compromise is worthy of debate. I'm
not sure I would agree that the "perfect speaker" is omnidirectional
given the objective is to recreate a sound of an event in one location
in a completely different (acoustically) location.
ScottW
Audio Empire
May 17, 2012, 9:05:13 PM5/17/12
to
On Thu, 17 May 2012 03:48:17 -0700, Gary Eickmeier wrote
(in article <a1k3bh...@mid.individual.net>):
You give yourself too much credit. This stuff isn't "theory" (as in an
untried hypothesis) this stuff is fact backed by mathematics and sound
acoustical physics. Your "notion" is backed by...what? Your own conviction
that you are right and the world of engineering is wrong? I'm afraid it takes
more than that to get your ideas accepted as fact. To even be considered, you
have to have bona fides. You haven't stated yours. A few non-controlled
experiments with some cheap microphones and some untutored listening is
simply not compelling. I'm not trying to put you down here, nor am I trying
to be unkind, but when one pontificates, one needs to have some credibility.
You certainly are within your rights to postulate any new theory you wish,
but without the proper foundation, you shouldn't get all defensive if nobody
follows you down that road.
> I have tried to point out that even among the "experts" there is no single
> stereo theory, all laid out and accepted by all engineers. There is just
> about as much variability in the audio engineering community as there is in
> religion. Look at loudspeaker design man. No one knows what the hell he is
> doing. There are dipoles, bipoles, omnis, and megaphones, line sources,
> point sources, wallspeakers and free standing speakers. No one has a clue
> how or why to do any of this, nor is there a guideline for any sort of
> "correct" design or theory of stereo.
That's a gross oversimplification. You have confused the fact that there are
many different ways to apply known electrical and acoustic principles with a
lack of knowledge and understanding on the part of those in the business.
This is not the case. Everybody knows what's needed , it's just that because
what's needed is ultimately impossible and so many faceted, that different
manufactures tend to concentrate on different parts of the overall puzzle.
For instance, manufacturer A might concentrate on getting a flat frequency
response across a wide room dispersion. Manufacturer B might concentrate on
image specificity while manufacturer C tries to get a realistic dynamic
range. Add to that the fact that some of these goals are, in reality,
mutually exclusive (for a speaker, not for real instruments playing in real
space).
IOW, why should anyone listen to you? You have made a number of errors in
your assumptions already. It's fine that you have ideas, but without a
grounding in physics and the experience to go along with it, you are bound to
go off the track at some point.
I had no comments on the rest of it.
(in article <a1k3bh...@mid.individual.net>):
untried hypothesis) this stuff is fact backed by mathematics and sound
acoustical physics. Your "notion" is backed by...what? Your own conviction
that you are right and the world of engineering is wrong? I'm afraid it takes
more than that to get your ideas accepted as fact. To even be considered, you
have to have bona fides. You haven't stated yours. A few non-controlled
experiments with some cheap microphones and some untutored listening is
simply not compelling. I'm not trying to put you down here, nor am I trying
to be unkind, but when one pontificates, one needs to have some credibility.
You certainly are within your rights to postulate any new theory you wish,
but without the proper foundation, you shouldn't get all defensive if nobody
follows you down that road.
> I have tried to point out that even among the "experts" there is no single
> stereo theory, all laid out and accepted by all engineers. There is just
> about as much variability in the audio engineering community as there is in
> religion. Look at loudspeaker design man. No one knows what the hell he is
> doing. There are dipoles, bipoles, omnis, and megaphones, line sources,
> point sources, wallspeakers and free standing speakers. No one has a clue
> how or why to do any of this, nor is there a guideline for any sort of
> "correct" design or theory of stereo.
many different ways to apply known electrical and acoustic principles with a
lack of knowledge and understanding on the part of those in the business.
This is not the case. Everybody knows what's needed , it's just that because
what's needed is ultimately impossible and so many faceted, that different
manufactures tend to concentrate on different parts of the overall puzzle.
For instance, manufacturer A might concentrate on getting a flat frequency
response across a wide room dispersion. Manufacturer B might concentrate on
image specificity while manufacturer C tries to get a realistic dynamic
range. Add to that the fact that some of these goals are, in reality,
mutually exclusive (for a speaker, not for real instruments playing in real
space).
>
> Nor am I just entering the room. I have been studying this stuff for almost
> 30 years now.
But what are your credentials that make your "study" worthy of attention?
> Nor am I just entering the room. I have been studying this stuff for almost
> 30 years now.
IOW, why should anyone listen to you? You have made a number of errors in
your assumptions already. It's fine that you have ideas, but without a
grounding in physics and the experience to go along with it, you are bound to
go off the track at some point.
Gary Eickmeier
May 18, 2012, 7:27:58 PM5/18/12
to
difficult and controversial topic. Audio Empire is a great source - at least
it seems that way, from his writing, but I know not who he is, what
credentials he has, if that matters so much to him - but he seems to be
figuratively sticking his fingers in his ears, shutting his eyes, and
erecting Engineers Club, Members Only signs all around his cubicle. That is
not constructive, and avoids a lot of discussion that I was hoping he could
handle. I have run into this time and time again.
Maybe I am Chicken Little, making waves about a completely unimportant or
nonexistent problem. Maybe not. I do not have an engineering degree - but
that hasn't stopped a lot of "experts" in the field of audio who are making
products that have no real merit. Audio is a funny subject. It's like, it's
invisible and completely subjective, so you can say almost anything you want
about various aspects of it and you might sell something. I realize that I
need to "do the work" and prove some of my ideas with experiments with
armies of college students filling out forms, blind listening tests, and
testimonials from other "experts."
I tried mightily last year, when Siegfried Linkwitz asked a few innocent
questions, questions that should have been answered maybe 60 years ago and
have not. It was called The Linkwitz Challenge, and was asked in an AES
paper at a convention a couple of years ago.
www.linkwitzlab.com/AES-NY'09/The%20Challenge.pdf
Our audio club responded, so I had my chance and took it. I almost achieved
some street cred with the preliminary result of
http://home.provide.net/~djcarlst/SLReport10.05.pdf
but then they went on and somehow got the Behringer speakers to come out on
top of even the Orions. I tried to point out some flaws in the test
procedures, but they would have none of it, declared me a lunatic and a
wacko for my ideas, so I resigned from the club and have been trying other
paths ever since. Those cheezy Radio Shack speakers were actually the third
prototypes that I have made, but I am not very good at speaker building (the
engineering part of it), so I am not ready to parade them in front of my own
test subjects or take them to the next AES convention yet.
Even if I did, even if I made the perfect mousetrap, what would happen? They
may make a splash for a year or two, then the industry at large would be
pissed because I have shown them how to make better sound for a lot lower
price and profit margin, and I would be badmouthed by all the high end
dealers and villified in the press.
So if I have been once again shot down, I apologize and will shut up again
unless and until poked by some other questions that someone wonders about in
some area of speaker imaging or realism of reproduction. Audio Empire has
been very communicative and forthcoming, and I believe he allowed me to send
some papers and read them and maybe some of my experimental recordings, for
which I thank him. I have enjoyed this discussion and a brief soapbox and
will answer anyone who writes to me, but I guess I better get off the pot
for a while again and go back into my cave.
Gary Eickmeier
Audio Empire
May 18, 2012, 11:13:24 PM5/18/12
to
On Fri, 18 May 2012 16:27:58 -0700, Gary Eickmeier wrote
(in article <a1o47u...@mid.individual.net>):
> ScottW wrote:
>> On May 17, 3:48 am, "Gary Eickmeier" <geick...@tampabay.rr.com> wrote:
>
>> The conversation is going to break down into hyperbole (or perhaps
>> already has).
>> Speaker design is a series of compromises and each design path has a
>> different set. Many of these are to address characteristics of
>> different rooms and/or listener preference.
>>
>> I would agree that the choice of compromise is worthy of debate. I'm
>> not sure I would agree that the "perfect speaker" is omnidirectional
>> given the objective is to recreate a sound of an event in one location
>> in a completely different (acoustically) location.
>
> Thanks Scotty. This is, at least, the beginnings of a conversation about a
> difficult and controversial topic. Audio Empire is a great source - at least
> it seems that way, from his writing, but I know not who he is, what
> credentials he has, if that matters so much to him - but he seems to be
> figuratively sticking his fingers in his ears, shutting his eyes, and
> erecting Engineers Club, Members Only signs all around his cubicle. That is
> not constructive, and avoids a lot of discussion that I was hoping he could
> handle. I have run into this time and time again.
>
> Maybe I am Chicken Little, making waves about a completely unimportant or
> nonexistent problem.
That's not it at all. Your problem is, and I have said this before. From what
you have written, I have no confidence that you have even the slightest clue
about what you are talking about. You remind me of the guy on an "alien
encounters" type TV show who was trying to convince the viewers that an alien
atomic explosion, not a meteor, wiped out the dinosaurs. As "proof" he said
that the mounted skeletons of dinosaurs found in museums were all painted
with "lead paint" so that the museum's patrons wouldn't get a dose of the
radiation left over from that explosion. When he made that comment, I knew
that the guy had no credibility. First of all, and probably most importantly,
the mounted skeletons in museums are not the actual fossils anyway, because
being rock (not bone) they would be too heavy to stand-up in a mount. Display
skeletons are fiberglass "bones" made from the casts of the original fossils
(and the older ones are likely shellacked papier mache). Secondly not being
bone (it having long since disintegrated while being replaced with minerals)
would no longer be radioactive even if it WERE when the animal died. And
finally, were the "bones" radioactive, no coating of "lead paint" would
shield the patrons from the radioactivity. No, I don't know the guy who made
these outlandish claims, he might be a nice guy and a smart guy, but just
that from WHAT HE SAID, I know that he had no knowledge of the subject upon
which he was pontificating.
> Maybe not. I do not have an engineering degree - but
> that hasn't stopped a lot of "experts" in the field of audio who are making
> products that have no real merit.
But you aren't selling a product. You are "selling" a theory, that from what
I have gleaned from you posts and your posted "white paper", you lack the
knowledge to actually be able to formulate.
> Audio is a funny subject. It's like, it's
> invisible and completely subjective, so you can say almost anything you want
> about various aspects of it and you might sell something.
Sure, people sell green pens and funny looking free-form wooden sculptures
that when placed in the listening space, supposedly tame the room. People
also sell digital clocks that "miraculously" clean up the power line, and
exotic wooden blocks that, when set on top of components make them sound
"better." And the gullible buy these things and convince themselves that it
was money well spent. But people like me don't buy them because we know that
they have no scientific basis behind them and that they not only don't work,
they CANNOT work. Pretending that we don't know everything there is to know
about sound as a basis for these magic nostrums, might fool the untutored,
but those of us with a solid background in engineering and physics simply
know better.
> I realize that I
> need to "do the work" and prove some of my ideas with experiments with
> armies of college students filling out forms, blind listening tests, and
> testimonials from other "experts."
It might help if you could show a mathematical model of your "theories" and I
encourage you to do so.
>
(in article <a1o47u...@mid.individual.net>):
> ScottW wrote:
>> On May 17, 3:48 am, "Gary Eickmeier" <geick...@tampabay.rr.com> wrote:
>
>> The conversation is going to break down into hyperbole (or perhaps
>> already has).
>> Speaker design is a series of compromises and each design path has a
>> different set. Many of these are to address characteristics of
>> different rooms and/or listener preference.
>>
>> I would agree that the choice of compromise is worthy of debate. I'm
>> not sure I would agree that the "perfect speaker" is omnidirectional
>> given the objective is to recreate a sound of an event in one location
>> in a completely different (acoustically) location.
>
> Thanks Scotty. This is, at least, the beginnings of a conversation about a
> difficult and controversial topic. Audio Empire is a great source - at least
> it seems that way, from his writing, but I know not who he is, what
> credentials he has, if that matters so much to him - but he seems to be
> figuratively sticking his fingers in his ears, shutting his eyes, and
> erecting Engineers Club, Members Only signs all around his cubicle. That is
> not constructive, and avoids a lot of discussion that I was hoping he could
> handle. I have run into this time and time again.
>
> Maybe I am Chicken Little, making waves about a completely unimportant or
> nonexistent problem.
you have written, I have no confidence that you have even the slightest clue
about what you are talking about. You remind me of the guy on an "alien
encounters" type TV show who was trying to convince the viewers that an alien
atomic explosion, not a meteor, wiped out the dinosaurs. As "proof" he said
that the mounted skeletons of dinosaurs found in museums were all painted
with "lead paint" so that the museum's patrons wouldn't get a dose of the
radiation left over from that explosion. When he made that comment, I knew
that the guy had no credibility. First of all, and probably most importantly,
the mounted skeletons in museums are not the actual fossils anyway, because
being rock (not bone) they would be too heavy to stand-up in a mount. Display
skeletons are fiberglass "bones" made from the casts of the original fossils
(and the older ones are likely shellacked papier mache). Secondly not being
bone (it having long since disintegrated while being replaced with minerals)
would no longer be radioactive even if it WERE when the animal died. And
finally, were the "bones" radioactive, no coating of "lead paint" would
shield the patrons from the radioactivity. No, I don't know the guy who made
these outlandish claims, he might be a nice guy and a smart guy, but just
that from WHAT HE SAID, I know that he had no knowledge of the subject upon
which he was pontificating.
> Maybe not. I do not have an engineering degree - but
> that hasn't stopped a lot of "experts" in the field of audio who are making
> products that have no real merit.
I have gleaned from you posts and your posted "white paper", you lack the
knowledge to actually be able to formulate.
> Audio is a funny subject. It's like, it's
> invisible and completely subjective, so you can say almost anything you want
> about various aspects of it and you might sell something.
that when placed in the listening space, supposedly tame the room. People
also sell digital clocks that "miraculously" clean up the power line, and
exotic wooden blocks that, when set on top of components make them sound
"better." And the gullible buy these things and convince themselves that it
was money well spent. But people like me don't buy them because we know that
they have no scientific basis behind them and that they not only don't work,
they CANNOT work. Pretending that we don't know everything there is to know
about sound as a basis for these magic nostrums, might fool the untutored,
but those of us with a solid background in engineering and physics simply
know better.
> I realize that I
> need to "do the work" and prove some of my ideas with experiments with
> armies of college students filling out forms, blind listening tests, and
> testimonials from other "experts."
encourage you to do so.
>
ScottW
May 19, 2012, 2:16:35 PM5/19/12
to
adjustment for the tweeters is critical to in room response. I don't
know how you set it and ship it to another location and leave it
without adjustment for best results.
I'd also say not using a sub with the Orions is not really apples to
apples. They probably have much better bass than either of the
competitors but still benefit from a sub if you're looking for solid
bottom octave output.
The criteria is also interesting. I'd forego the last one (freedom of
movement) entirely. I'm prefectly willing to settle into a great
sweet spot.
I'd also wonder about the ability of the judges to have a common
perspective on the criteria. To me..1 and 2 are very likely highly
correlated.
I think the real subjective part of speaker evaluation is simply in
establishing the evaluation criteria. These criteria are purely
subjective based on human perception. I'd prefer something measurable
with established correlation to human perception. For
example...radiation pattern. What should it be? I don't think there
is a simple agreed answer. Omidirectional isn't it IMO. And as the
thread on a small room solution showed, opinions will vary.
But once the criteria is established....then measuring objectively
isn't an issue.
Engineers will always strive for a path out of the subjective realm
but the final arbiter in audio is always subjective.
ScottW
Andrew Haley
May 20, 2012, 10:33:35 AM5/20/12
to
Gary Eickmeier <geic...@tampabay.rr.com> wrote:
> ScottW wrote:
>> On May 17, 3:48 am, "Gary Eickmeier" <geick...@tampabay.rr.com> wrote:
>
>> The conversation is going to break down into hyperbole (or perhaps
>> already has).
>> Speaker design is a series of compromises and each design path has a
>> different set. Many of these are to address characteristics of
>> different rooms and/or listener preference.
>>
>> I would agree that the choice of compromise is worthy of debate. I'm
>> not sure I would agree that the "perfect speaker" is omnidirectional
>> given the objective is to recreate a sound of an event in one location
>> in a completely different (acoustically) location.
>
> Thanks Scotty. This is, at least, the beginnings of a conversation
> about a difficult and controversial topic. Audio Empire is a great
> source - at least it seems that way, from his writing, but I know
> not who he is, what credentials he has, if that matters so much to
> him - but he seems to be figuratively sticking his fingers in his
> ears, shutting his eyes, and erecting Engineers Club, Members Only
> signs all around his cubicle.
I don't think that's it exactly. He's saying look, you have all these
> ScottW wrote:
>> On May 17, 3:48 am, "Gary Eickmeier" <geick...@tampabay.rr.com> wrote:
>
>> The conversation is going to break down into hyperbole (or perhaps
>> already has).
>> Speaker design is a series of compromises and each design path has a
>> different set. Many of these are to address characteristics of
>> different rooms and/or listener preference.
>>
>> I would agree that the choice of compromise is worthy of debate. I'm
>> not sure I would agree that the "perfect speaker" is omnidirectional
>> given the objective is to recreate a sound of an event in one location
>> in a completely different (acoustically) location.
>
> Thanks Scotty. This is, at least, the beginnings of a conversation
> about a difficult and controversial topic. Audio Empire is a great
> source - at least it seems that way, from his writing, but I know
> not who he is, what credentials he has, if that matters so much to
> him - but he seems to be figuratively sticking his fingers in his
> ears, shutting his eyes, and erecting Engineers Club, Members Only
> signs all around his cubicle.
opinions, and these guys over here have opinions too, but they also
have data and reserach studies. It's not about who is qualified to
have an opinion; everyone is.
> That is not constructive, and avoids a lot of discussion that I was
> hoping he could handle. I have run into this time and time again.
>
> Maybe I am Chicken Little, making waves about a completely
> unimportant or nonexistent problem. Maybe not. I do not have an
> engineering degree - but that hasn't stopped a lot of "experts" in
> the field of audio who are making products that have no real
> merit. Audio is a funny subject. It's like, it's invisible and
> completely subjective, so you can say almost anything you want about
> various aspects of it and you might sell something. I realize that I
> need to "do the work" and prove some of my ideas with experiments
> with armies of college students filling out forms, blind listening
> tests, and testimonials from other "experts."
The questions I have to ask are: what kind of evidence would it take
to convince you that you were wrong? How would you design an
experiment that has the best chance to refute your own theories as
convincingly as possible?
Andrew.
Gary Eickmeier
May 20, 2012, 10:36:43 PM5/20/12
to
Andrew Haley wrote:
> I don't think that's it exactly. He's saying look, you have all these
> opinions, and these guys over here have opinions too, but they also
> have data and reserach studies. It's not about who is qualified to
> have an opinion; everyone is.
What data and research studies? I have pointed out that no one has answered
> I don't think that's it exactly. He's saying look, you have all these
> opinions, and these guys over here have opinions too, but they also
> have data and reserach studies. It's not about who is qualified to
> have an opinion; everyone is.
Linkwitz's questions in all of audio history yet. He asked about what I call
"The Big Three" of radiation pattern, speaker positioning, and room
acoustics. The simple question was, which radiation pattern is most correct,
which room positioning of speakers, what sort of room treatment is most
correct for the establishment of the most realistic AS, or Auditory Scene
(as compared to live sound). I have also pointed out that there is little or
no agreement among the "experts" about any of these things. There is no
basic stereo theory, or paradigm or model of how it should be done in
systems with the highest goals - namely, the realistic reproduction of
auditory perspective.
I searched all through Floyd Toole's new book and found nothing on this
subject, nothing that answered Linkwitz's questions.
> Well, yes.
>
> The questions I have to ask are: what kind of evidence would it take
> to convince you that you were wrong? How would you design an
> experiment that has the best chance to refute your own theories as
> convincingly as possible?
Three are not audible. You might have a variety of speakers from dipoles to
omnis to direct firing, you might place them up against the wall, out into
the room, or in the corners. You might have a room that is highly reflective
at the speaker end, or highly absorptive. If you can show that none of these
factors is audible, then I would have to go back into my cave and admit
defeat.
Gary Eickmeier
Gary Eickmeier
May 20, 2012, 10:58:47 PM5/20/12
to
"Audio Empire" <audio_...@comcast.net> wrote in message
news:jp734...@news1.newsguy.com...
> That's not it at all. Your problem is, and I have said this before. From
> what
> you have written, I have no confidence that you have even the slightest
> clue
> about what you are talking about.
feel that way? Argue the subject, if you are so knowledgeable.
> But you aren't selling a product. You are "selling" a theory, that from
> what
> I have gleaned from you posts and your posted "white paper", you lack the
> knowledge to actually be able to formulate.
nothing erroneous, or even all that controversial. I have explained in
greater detail what William Snow said, that stereo is a field-type system,
in which we attempt to reconstruct the fields that existed in the original.
The basic idea is that you place speakers around the room where you want the
sounds to come from. Have you heard about surround sound? Three speakers are
placed up front, arranged in geometrecally similar positions to the
positions of the instruments that were recorded. Surround speakers are
placed where ambient fields belong. Image Model Theory goes into greater
detail about the frontal soundstage, explaining how to arrange the radiation
pattern, room positioning, and reflective qualities of the walls to mimic
the spatial patterns of the original. The main point is that the spatial
qualities of speakers and rooms are audible, such as between corner horns
and MBLs or Quads pulled out from the walls. I suggest a model that you can
use to determine which arrangement is more realistic, that the answer to
what causes perceptual qualities of stereo does not come from the direct
sound alone, as has been thought by most writers in the past. I encourage
you to study auditory perspective theory from the standpoint of the total
horizontal acoustical situation, illustrated by what is called the image
model of the room and speakers. All of these things have been talked around
in the past, but not tied together into a cohesive theory to explain why
something sounds the way it does in more visual terms.
See if you can go over it all again and tell me anything I said that is
wrong.
> Sure, people sell green pens and funny looking free-form wooden sculptures
> that when placed in the listening space, supposedly tame the room. People
> also sell digital clocks that "miraculously" clean up the power line, and
> exotic wooden blocks that, when set on top of components make them sound
> "better." And the gullible buy these things and convince themselves that
> it
> was money well spent. But people like me don't buy them because we know
> that
> they have no scientific basis behind them and that they not only don't
> work,
> they CANNOT work. Pretending that we don't know everything there is to
> know
> about sound as a basis for these magic nostrums, might fool the untutored,
> but those of us with a solid background in engineering and physics simply
> know better.
> It might help if you could show a mathematical model of your "theories"
> and I
> encourage you to do so.
STOP IT! This is not mathematical! It is conceptual! You have just GOT to
> and I
> encourage you to do so.
get this material. Or at least talk to me so I can tell what step is missing
from my explanation.
>>
OK, you stopped short again. I told about an experiment that I participated
in that helped answer Linkwitz's very basic questions, in which I was quite
successful.
Talk to me.
Gary Eickmeier
PS - suggestion, to throw the ball back into your court so you can
straighten me right out:
YOU tell ME what are the answers to Linkwitz's challenge questions. What is
the corrct radiation pattern, speaker positioning, and room acoustical
qualities for the greatest realism in the reproduction of the Auditory
Scene, or AS? Why? How do you know? Have you thought about it much before,
or do you think that "The Big Three" are not audible?
Andrew Haley
May 21, 2012, 9:03:02 AM5/21/12
to
Gary Eickmeier <geic...@tampabay.rr.com> wrote:
positioning, and room acoustics are not audible. That is something
about which there is no disagreement.
> You might have a variety of speakers from dipoles to omnis to direct
> firing, you might place them up against the wall, out into the room,
> or in the corners. You might have a room that is highly reflective
> at the speaker end, or highly absorptive. If you can show that none
> of these factors is audible, then I would have to go back into my
> cave and admit defeat.
So, nothing short of proving that radiation pattern, speaker
positioning, and room acoustics are not audible will make you doubt
your theories. But we already know that thse things are audible, so
there is no experiment that could be done by anyone that would make a
diference to you.
Andrew.
> Andrew Haley wrote:
>
>> The questions I have to ask are: what kind of evidence would it take
>> to convince you that you were wrong? How would you design an
>> experiment that has the best chance to refute your own theories as
>> convincingly as possible?
>
> That one is simple Andrew. Just construct a test that shows that the Big
> Three are not audible.
Excuse me! No-one is claiming that radiation pattern, speaker
>
>> The questions I have to ask are: what kind of evidence would it take
>> to convince you that you were wrong? How would you design an
>> experiment that has the best chance to refute your own theories as
>> convincingly as possible?
>
> That one is simple Andrew. Just construct a test that shows that the Big
> Three are not audible.
positioning, and room acoustics are not audible. That is something
about which there is no disagreement.
> You might have a variety of speakers from dipoles to omnis to direct
> firing, you might place them up against the wall, out into the room,
> or in the corners. You might have a room that is highly reflective
> at the speaker end, or highly absorptive. If you can show that none
> of these factors is audible, then I would have to go back into my
> cave and admit defeat.
positioning, and room acoustics are not audible will make you doubt
your theories. But we already know that thse things are audible, so
there is no experiment that could be done by anyone that would make a
diference to you.
Andrew.
Gary Eickmeier
May 21, 2012, 10:30:33 AM5/21/12
to
Andrew Haley wrote:
> So, nothing short of proving that radiation pattern, speaker
> positioning, and room acoustics are not audible will make you doubt
> your theories. But we already know that thse things are audible, so
> there is no experiment that could be done by anyone that would make a
> diference to you.
>
> Andrew.
Er - excuse ME, but then you agree with me. I have said that those factors
> So, nothing short of proving that radiation pattern, speaker
> positioning, and room acoustics are not audible will make you doubt
> your theories. But we already know that thse things are audible, so
> there is no experiment that could be done by anyone that would make a
> diference to you.
>
> Andrew.
are audible and we should study the reproduction problem from the standpoint
of what those do to the sound. Linkwitz asked the same question, is there a
way to distinguish which variations of those factors lead to greatest
realism in the reproduction.
But there is a way to visualize the whole situation, a method that is time
honored and not controversial, and it is called image modeling. My
contribution is to propose that we study the reproduction problem from the
standpoint of comparing the image model of the live event to that of the
reproduction system of speakers and room. Most studies about stereo have
dealt with only the direct sound radiated from a pair or a line of speakers.
I point out that this approach sees the problem as a "windowing" or
portaling process, but that it might operate more like a model of the real
thing in which we should pay attention to the sound patterns produced in the
room by the full model, not just the direct field.
I relate my success with this approach both in my own system and in an
experiment conducted by my audio club.
I fully realize that all the talk in the world will not prove any of it to
you just by reading what I have written, but you may have already
experienced the effect that I am talking about in your listening experience.
Writers and audiophiles talk about the "floating" of images, depth of
soundstaging, and speakers disappearing. These are some of the effects that
Linkwitz experiences in his system, with its highly reflective room and his
equi-omni radiation pattern and his speakers pulled out into the room.
The speaker disappearing act is caused by a simple image shift toward the
reflected sound from behind the actual speakers. An aerial image is formed
in the region behind the speakers, getting the sound OUT of the speaker
boxes and creating the unmistakable impression of the musicians being right
there in front of you performing in your room, rather than sounding like
they are flat cartoons coming from the speakers and strung on a clothesline
between the speakers, with no depth or dimensionality. When done right, the
reflected sound that was recorded can seem to come from a broad set of
incident angles that are wider than the separation of the actual speakers,
lending the spaciousness that direct and reflecting speakers are famous for.
The combined effect gives the impression of the performers in front of you
along with turning your room into a model of the original hall, especially
when surround speakers are incorporated. If it is a tight and dry recording,
they are here. If it has some hall ambience recorded, they are here and so
is most of the acoustical environment of the original, displayed where it
belongs deep behind the performers and super wide beside and behind you.
You may have heard this effect with Quads, Martin Logans, MBLs, or even yes,
Bose 901s if placed correctly. I don't know if audiophiles think that this
effect is caused by point sourcedness, time alignment, or magic, but I am
here to tell you what does cause it and how to incorporate that into basic
stereo theory and perfect it.
Without an understanding of what causes all this three dimensionality and
speakers disappearing, you are just as liable to place your speakers right
up against the walls, or in the corners of your room, and never experience
what I am talking about.
I discovered it by accident and have been studying it for close to 30 years
now. You can fight me about it or study it further and try it youself, I
don't care, I'm just trying to explain something about genuinely audible
effects from an angle that has not been examined this closely before.
Thank you for your patience!
Gary Eickmeier, aka Chicken Little
Andrew Haley
May 21, 2012, 11:32:37 AM5/21/12
to
Gary Eickmeier <geic...@tampabay.rr.com> wrote:
> Andrew Haley wrote:
>
>> So, nothing short of proving that radiation pattern, speaker
>> positioning, and room acoustics are not audible will make you doubt
>> your theories. But we already know that thse things are audible, so
>> there is no experiment that could be done by anyone that would make a
>> diference to you.
>
> Andrew Haley wrote:
>
>> So, nothing short of proving that radiation pattern, speaker
>> positioning, and room acoustics are not audible will make you doubt
>> your theories. But we already know that thse things are audible, so
>> there is no experiment that could be done by anyone that would make a
>> diference to you.
>
> Er - excuse ME, but then you agree with me.
Insamuch as I agree that these factors change the sound, yes. If
that's all that your theories amount to, we're done. But I don't
think it is.
> I have said that those factors are audible and we should study the
> reproduction problem from the standpoint of what those do to the
> sound. Linkwitz asked the same question, is there a way to
> distinguish which variations of those factors lead to greatest
> realism in the reproduction.
>
> But there is a way to visualize the whole situation, a method that
> is time honored and not controversial, and it is called image
> modeling. My contribution is to propose that we study the
> reproduction problem from the standpoint of comparing the image
> model of the live event to that of the reproduction system of
> speakers and room. Most studies about stereo have dealt with only
> the direct sound radiated from a pair or a line of speakers. I
> point out that this approach sees the problem as a "windowing" or
> portaling process, but that it might operate more like a model of
> the real thing in which we should pay attention to the sound
> patterns produced in the room by the full model, not just the direct
> field.
have to model the room. Toole, with whom you say you have some
disagreement, does not disagree with this, and talks at length about
the beneficial effects of room reflections, particularly on apparent
source width.
> Without an understanding of what causes all this three
> dimensionality and speakers disappearing, you are just as liable to
> place your speakers right up against the walls, or in the corners of
> your room, and never experience what I am talking about.
Again, I'm going to ask the question: what experimental results would
it take to convince you that Toole at al are right, and you are wrong?
Note that Toole goes to some length to explain why dead rooms are far
from ideal, the recordiong indistry's preference for them is a
historical mistake. The difference, as far as I can see it, is that
you prefer a greater amount of reflected sound, and you have some
uncommon theories about speaker placement.
Andrew.
Audio Empire
May 21, 2012, 7:49:38 PM5/21/12
to
On Mon, 21 May 2012 07:30:33 -0700, Gary Eickmeier wrote
(in article <a1v1s9...@mid.individual.net>):
> The speaker disappearing act is caused by a simple image shift toward the
> reflected sound from behind the actual speakers. An aerial image is formed
> in the region behind the speakers, getting the sound OUT of the speaker
> boxes and creating the unmistakable impression of the musicians being right
> there in front of you performing in your room, rather than sounding like
> they are flat cartoons coming from the speakers and strung on a clothesline
> between the speakers, with no depth or dimensionality.
You speak as if this is a characteristic inherent in the speaker itself.
Well, I agree that the speaker must be able to image well and "throw" a wide
and deep soundstage, BUT - and this is all important - if the information is
NOT there on the recording in the first place, even the world's best imaging
speakers won't be able to produce the illusion to which you refer. Take most
any classical recording from the mid-sixties to the late eighties and the
great majority of recordings made since then, and there is NO imaging
information on the recording. Most are, as you so aptly put it, a series of
"flat cartoons" 'Strung on a clothesline." This is because most recordings
are multi-miked, multi-track travesties and sound simply dreadful from an
imaging perspective. I believe that one of the reasons that audiophiles still
revere recordings made more than 55 years ago by the likes of Lewis Layton,
and Richard Mohr at RCA Victor, Bob Fine, Wilma Fine and Bob Eberenz at
Mercury, and Bert Whyte for Everest is because these recordings were made
with simple, two or three mike setups directly to tape with no electronic
"futzing" between the mikes and the tape. Many of these recordings have the
soundstage information that allows for good, realistic imaging (assuming that
the playback system is up to the task).
Now, it's true that today's audiophile is more likely to listen to rock music
than he is to listen to classical, and I've always found this to be amusing.
They talk of imaging while listening to recordings which not only don't have
any imaging, they CAN'T have any because the instruments themselves are
individually recorded, not the space which the instruments inhabit. In fact,
in many rock and pop recordings, all of the acoustic instruments (saxes,
horns, woodwinds, strings), if any, are "frapped" (recorded using a contact
microphone where the microphone is designed to be attached directly to the
body of the instrument and therefore picks-up the sound of the instrument
through the instrument itself, not through the air) and then laid down on
it's own isolated track to be mixed into the finished recording later. In
these cases, the individual tracks are pan-potted into the final mix so that
the instruments ARE lined up as if on a clothesline. and due to the extreme
close-up perspective afforded by "frapping" are cartoon cut-outs of the
instruments in question because the space that the instrument occupies wasn't
captured along with the instrument itself.
"Classic" stereo jazz recordings fare little better. Each instrument is
again miked separately, then mixed-down to three tracks. right, left, and a
phantom center channel (where the soloist or principle player (instrumental
or vocalist) is invariably placed). There's no real imaging here either. One
of the things that drove me, originally, to start recording was my desire for
"real" stereo recordings, done right. Since one couldn't rely on the major
labels to do it right, I figured I'd be better off "rolling my own". The
results have been pretty spectacular over the years, and I've rarely heard
anything that sounds as good or images as well on commercial releases. One
would think that with all the resources at the disposal of the major record
companies that they could do at least as well as I can with my modest
resources, but the don't.
(in article <a1v1s9...@mid.individual.net>):
> The speaker disappearing act is caused by a simple image shift toward the
> reflected sound from behind the actual speakers. An aerial image is formed
> in the region behind the speakers, getting the sound OUT of the speaker
> boxes and creating the unmistakable impression of the musicians being right
> there in front of you performing in your room, rather than sounding like
> they are flat cartoons coming from the speakers and strung on a clothesline
> between the speakers, with no depth or dimensionality.
Well, I agree that the speaker must be able to image well and "throw" a wide
and deep soundstage, BUT - and this is all important - if the information is
NOT there on the recording in the first place, even the world's best imaging
speakers won't be able to produce the illusion to which you refer. Take most
any classical recording from the mid-sixties to the late eighties and the
great majority of recordings made since then, and there is NO imaging
information on the recording. Most are, as you so aptly put it, a series of
"flat cartoons" 'Strung on a clothesline." This is because most recordings
are multi-miked, multi-track travesties and sound simply dreadful from an
imaging perspective. I believe that one of the reasons that audiophiles still
revere recordings made more than 55 years ago by the likes of Lewis Layton,
and Richard Mohr at RCA Victor, Bob Fine, Wilma Fine and Bob Eberenz at
Mercury, and Bert Whyte for Everest is because these recordings were made
with simple, two or three mike setups directly to tape with no electronic
"futzing" between the mikes and the tape. Many of these recordings have the
soundstage information that allows for good, realistic imaging (assuming that
the playback system is up to the task).
Now, it's true that today's audiophile is more likely to listen to rock music
than he is to listen to classical, and I've always found this to be amusing.
They talk of imaging while listening to recordings which not only don't have
any imaging, they CAN'T have any because the instruments themselves are
individually recorded, not the space which the instruments inhabit. In fact,
in many rock and pop recordings, all of the acoustic instruments (saxes,
horns, woodwinds, strings), if any, are "frapped" (recorded using a contact
microphone where the microphone is designed to be attached directly to the
body of the instrument and therefore picks-up the sound of the instrument
through the instrument itself, not through the air) and then laid down on
it's own isolated track to be mixed into the finished recording later. In
these cases, the individual tracks are pan-potted into the final mix so that
the instruments ARE lined up as if on a clothesline. and due to the extreme
close-up perspective afforded by "frapping" are cartoon cut-outs of the
instruments in question because the space that the instrument occupies wasn't
captured along with the instrument itself.
"Classic" stereo jazz recordings fare little better. Each instrument is
again miked separately, then mixed-down to three tracks. right, left, and a
phantom center channel (where the soloist or principle player (instrumental
or vocalist) is invariably placed). There's no real imaging here either. One
of the things that drove me, originally, to start recording was my desire for
"real" stereo recordings, done right. Since one couldn't rely on the major
labels to do it right, I figured I'd be better off "rolling my own". The
results have been pretty spectacular over the years, and I've rarely heard
anything that sounds as good or images as well on commercial releases. One
would think that with all the resources at the disposal of the major record
companies that they could do at least as well as I can with my modest
resources, but the don't.
Sebastian Kaliszewski
May 22, 2012, 7:18:05 PM5/22/12
to
Gary Eickmeier wrote:
[... large snip ...]
sampled at some predetermined points in space, and those points and in fact
acoustical transformation assigned with all of them do differ significantly
among different recordings. And anyway, such a transformation loses vast
majority of the information -- for a start it transforms (projects) 3
dimensional data into just single dimension.
> What we have done is dispatched the microphones
> up to the orchestra, recorded the musicians and the soundstage surrounding
> them, and brought back the sound to be played again from entirely within our
> room, not from outside with holes punched in the walls so we can hear it.
> This is quite a different thing, and it forces us for the first time to
> think of the listening room not as a nuisance variable but as the performing
> space itself. For better or for worse, the room must be thought of as an
> integral part of the sound, to be used to construct the same sort of spatial
> patterns that existed in the real concert hall, rather than fought with
> sound killing materials.
So far so good.
> I believe that this is for the better, because once
> we reconstruct the sound fields in the playhback room, all of the
> characteristics of live sound can be present, making the sound real and not
> a trick.
One litlle problem -- it might well be physically impossible.
> The stereophonic recording can be thought of as a concentrate, to
> be mixed with the playback acoustic in a way that models the reproduction
> after the real thing.
Recrating various sound fields from arbitrary events at different venues by just
two (or even 5 or 7 or 8) speakers is physically impossible. Period.
But our ears-brain system perceives only part of full physical reality of
acousting waves propagating in the space. Its fairly sensitive to some parts of
that reality, while being pretty insensitive to others. Thus here enters
psychoacoustics and all that masking, various sensitivituies for distinct
phenomenons and so on.
Certainly some aspects of soundfield characteristics are unimportant while
others are crucial for realistic presentation. So maybe, just maybe, after
prunning ale the unimportant stuff we could get some model which for our human
senses resempbles reality. But the reality might be such, that it's not possible
at all with less than 10 channels. In that sesond case we need to drop some
important characteristics to reduce degreees of freedom enough -- then all we
have is a trick, an illusion, and somewhat faulty one. My gut feeling is that
that second case is in fact true, but that's just my intuition and I might be
proven wrong.
> Although we must inevitably hear some of the
> listeining room along with the "flavor" of the recorded acoustic, the
> realism can be stunning.
But what's the basis of your claim. I read your white paper and what you wrote
here and probably some time ago stumbled upon something from you on some audio
forum(s)). What I miss is that actual theory you're talking about. You describe
how thing should be without showing how to reach tha goal nor even presenting
any argument that this goal is acheivable at all.
Your ideas about speaker directivity and placement such reflected images extend
the audio scene in a room which is typically (much) smaller than recorded
performance venue are all interesting but they do not for a theory. They are yet
another trick withing a big bag of tricks already known.
rgds
\SK
--
"Never underestimate the power of human stupidity" -- L. Lang
--
http://www.tajga.org -- (some photos from my travels)
[... large snip ...]
> Many people, especially audiophiles, have the impression that the recording
> contains a perfect image of the performance as witnessed from the best seat
> in the house. This may be true with binaural, but stereophonic is a very
> much different process. The problem with the above analogy is that it
> pictures the sound as having been "witnessed," or recorded, from the vantage
> point of the listener in the room suspended in the middle of the concert
> hall. This is not the case.
What is the case is that all we got is just a little part of a soundfield
> contains a perfect image of the performance as witnessed from the best seat
> in the house. This may be true with binaural, but stereophonic is a very
> much different process. The problem with the above analogy is that it
> pictures the sound as having been "witnessed," or recorded, from the vantage
> point of the listener in the room suspended in the middle of the concert
> hall. This is not the case.
sampled at some predetermined points in space, and those points and in fact
acoustical transformation assigned with all of them do differ significantly
among different recordings. And anyway, such a transformation loses vast
majority of the information -- for a start it transforms (projects) 3
dimensional data into just single dimension.
> What we have done is dispatched the microphones
> up to the orchestra, recorded the musicians and the soundstage surrounding
> them, and brought back the sound to be played again from entirely within our
> room, not from outside with holes punched in the walls so we can hear it.
> This is quite a different thing, and it forces us for the first time to
> think of the listening room not as a nuisance variable but as the performing
> space itself. For better or for worse, the room must be thought of as an
> integral part of the sound, to be used to construct the same sort of spatial
> patterns that existed in the real concert hall, rather than fought with
> sound killing materials.
> I believe that this is for the better, because once
> we reconstruct the sound fields in the playhback room, all of the
> characteristics of live sound can be present, making the sound real and not
> a trick.
> The stereophonic recording can be thought of as a concentrate, to
> be mixed with the playback acoustic in a way that models the reproduction
> after the real thing.
two (or even 5 or 7 or 8) speakers is physically impossible. Period.
But our ears-brain system perceives only part of full physical reality of
acousting waves propagating in the space. Its fairly sensitive to some parts of
that reality, while being pretty insensitive to others. Thus here enters
psychoacoustics and all that masking, various sensitivituies for distinct
phenomenons and so on.
Certainly some aspects of soundfield characteristics are unimportant while
others are crucial for realistic presentation. So maybe, just maybe, after
prunning ale the unimportant stuff we could get some model which for our human
senses resempbles reality. But the reality might be such, that it's not possible
at all with less than 10 channels. In that sesond case we need to drop some
important characteristics to reduce degreees of freedom enough -- then all we
have is a trick, an illusion, and somewhat faulty one. My gut feeling is that
that second case is in fact true, but that's just my intuition and I might be
proven wrong.
> Although we must inevitably hear some of the
> listeining room along with the "flavor" of the recorded acoustic, the
> realism can be stunning.
here and probably some time ago stumbled upon something from you on some audio
forum(s)). What I miss is that actual theory you're talking about. You describe
how thing should be without showing how to reach tha goal nor even presenting
any argument that this goal is acheivable at all.
Your ideas about speaker directivity and placement such reflected images extend
the audio scene in a room which is typically (much) smaller than recorded
performance venue are all interesting but they do not for a theory. They are yet
another trick withing a big bag of tricks already known.
rgds
\SK
--
"Never underestimate the power of human stupidity" -- L. Lang
--
http://www.tajga.org -- (some photos from my travels)
Gary Eickmeier
May 22, 2012, 9:51:10 PM5/22/12
to
"Audio Empire" <audio_...@comcast.net> wrote in message
news:jpeka...@news3.newsguy.com...
As I mentioned, if it is a tight and dry recording it gives a "they are
here" impression. In other words, no original acoustics recorded, it places
the instruments right in the environment of your listening room, like a
player piano or something. Those images will take a position the closest up
front that your system is capable of displaying, but still should not EVER
come from the speaker boxes themselves.
At the audio club I demonstrated this with the dry, mono recording of the
human voice outdoors. I transferred it to my laptop and processed it with
Audition so that it would pan from extreme right to extreme left chennel.
This was with my experimental speakers that were entered in The Challenge.
Most audio people would expect such a dry sound to image from one speaker to
the other and come from the speaker itself when at the channel extremes. So
to prove my point, I obtained an orange cone from Home Depot so that I could
place a visual where the audience perceived the sound to be coming from. I
started the recording at stage right, and when it got to the center I asked
them where the voice was. I placed the cone as directed until everyone
agreed. It ended up centered but a foot or two back behind the line of the
speakers. Same question when it got to stage extreme left. To their surprise
the voice was coming not from the speaker but from a foot behind the
speaker - unmistakably. To me, this proves the image shift, which slightly
defies the precedence principle. But even the textbooks say that if the
reflection is strong enough there will be an image shift.
This principle can be a very powerful tool in setting up your speaker system
for imaging, but if done wrong can be a disaster of Consumer Reports vs Bose
proportions. Bose did not give correct speaker positioning instructions in
the owner manual for the 901s, inviting disaster with a strongly negative
directivity speaker (strong reflected portion of its output). CR reported a
hole in the middle and stretched soloists, as did many audiophiles. If
correctly placed by accident, they could be impressive, but if you put them
too close to the walls all of the criticisms rear their ugly heads.
Draw an image model of the problem and you can see easily what is happening.
Move the speakers closer to the front wall and depth diminishes because the
reflected image speaker gets closer to the actual one. Move the speakers
wider, and the total image (or soundstage) becomes narrower! Place them
within a foot or two of the corners, and you get a "clustering" of acoustic
images that causes this hole in the middle and six foot wide soloists. I
threw caution to the winds one fine day and pulled my speakers out from the
walls and in to about 1/4 of the room width, and all of a sudden the sound
focused itself like a camera lens and there in front of me was the answer to
many questions.
I don't know where Andrew got the impression that I disagreed with Floyd on
something. What I said was that I read all through his book for the answers
to Linkwitz's very basic questions but couldn't find specific
recommendations on radiation pattern, speaker positioning or room acoustics
except to the extent that he agreed that reflected sound was necessary in
any audio setup. In fact, I wrote to him several times and asked him
directly about these questions, and also noted the many areas in his book
that supported my IMT. I was hoping for some sort of endorsement of my
writings, but it was not forthcoming. I have found that the well-known and
respected engineers will not commit themselves on paper to any outside
unsolicited ideas, especially off the beaten path ones like mine. I had a
nice, long talk on the phone with Siegfried, but he would not write that my
ideas were answers to his questions.
Same with Dr. Bose, in case you were wondering. I have tried to get him to
come out with an advanced, audiophile class 901 speaker with a slightly
different radiation pattern, but he is more interested in the mass market
than the small group that classifies themselves as audiophiles. And of
course it is the same as with unsolicited manuscripts sent to Hollywood
producers - they will not even be opened or acknowledged, for fear of
lawsuits if they use any of your material without paying you.
So I remain a voice crying in the wilderness. So fine.
Gary Eickmeier
Audio Empire
May 22, 2012, 10:44:32 PM5/22/12
to
On Tue, 22 May 2012 16:18:05 -0700, Sebastian Kaliszewski wrote
(in article <jph6r...@news6.newsguy.com>):
<snip>
>> Although we must inevitably hear some of the
> > listeining room along with the "flavor" of the recorded acoustic, the
> > realism can be stunning.
>
> But what's the basis of your claim. I read your white paper and what
> you wrote here and probably some time ago stumbled upon something
> from you on some audio forum(s)). What I miss is that actual
> theory you're talking about. You describe how thing should be
> without showing how to reach tha goal nor even presenting
> any argument that this goal is acheivable at all. Your ideas about
> speaker directivity and placement such reflected images extend the
> audio scene in a room which is typically (much) smaller than
> recorded performance venue are all interesting but they do not for
> a theory. They are yet another trick withing a big bag of tricks
> already known.
Well, that is certainly one of the problems with Mr. Eickmeier's
missives. The other, and the one I have been taking him to task over,
is that his "observations"(?) seem to totally ignore the other side of
the process; the recording.
There is no single type of recording that can be modeled by any single
speaker setup. There are as many different recording methods as there
are recording engineers/producers or, for that matter, recording
venues. Which is used for what circumstance depends upon many
different things, not the least of which is the engineer/producer's
"taste" (or more likely, lack of it) in sound. Since capturing
everything, just like reproducing everything, is impossible, people
tend to concentrate on those aspects of the sound that they feel are
important. Often what the recording people are trying to capture and
what the listener is trying to reproduce in his home are two different
things. For instance, if I'm a listener who really gets-off on
pin-point imaging and I have spent a small fortune putting together a
system that gets the imaging right at the expense of, perhaps, some
other characteristics that don't interest me as much (like, perhaps,
low bass) and I play a recording that's been made with 48 or more
tracks and a forest of microphones, then I'm not going to enjoy that
recording because it has no image. OTOH, if I like well reproduced,
clean treble and have designed my system to highlight that, and I play
a recording that has been made with microphones that are too bright
or a recording where the engineer has toned down the high frequencies
because he doesn't like "sparkling highs" , then that listener is not
going to get optimum sound from either one of those recordings on his
playback system. A speaker system that can give decent reproduction
irrespective of the recording or the recording venue, simply doesn't
exist and it can't exist. Even if one could buy the ultimate,
theoretical ideal of a speaker system, unless that ideal is carried
all the way back to the recording so that all the music one plays on
one's ideal playback system was captured with a theoretically ideal
microphone system and then recorded with totally transparent
electronics to a theoretically perfect recording device, all bets are
off and the system is still going to be fundamentally flawed. The kind
of control that I believe that Mr. Eickmeier is advocating here is
simply impossible because the variables are simply too many.
(in article <jph6r...@news6.newsguy.com>):
<snip>
>> Although we must inevitably hear some of the
> > listeining room along with the "flavor" of the recorded acoustic, the
> > realism can be stunning.
>
> But what's the basis of your claim. I read your white paper and what
> you wrote here and probably some time ago stumbled upon something
> from you on some audio forum(s)). What I miss is that actual
> theory you're talking about. You describe how thing should be
> without showing how to reach tha goal nor even presenting
> any argument that this goal is acheivable at all. Your ideas about
> speaker directivity and placement such reflected images extend the
> audio scene in a room which is typically (much) smaller than
> recorded performance venue are all interesting but they do not for
> a theory. They are yet another trick withing a big bag of tricks
> already known.
missives. The other, and the one I have been taking him to task over,
is that his "observations"(?) seem to totally ignore the other side of
the process; the recording.
There is no single type of recording that can be modeled by any single
speaker setup. There are as many different recording methods as there
are recording engineers/producers or, for that matter, recording
venues. Which is used for what circumstance depends upon many
different things, not the least of which is the engineer/producer's
"taste" (or more likely, lack of it) in sound. Since capturing
everything, just like reproducing everything, is impossible, people
tend to concentrate on those aspects of the sound that they feel are
important. Often what the recording people are trying to capture and
what the listener is trying to reproduce in his home are two different
things. For instance, if I'm a listener who really gets-off on
pin-point imaging and I have spent a small fortune putting together a
system that gets the imaging right at the expense of, perhaps, some
other characteristics that don't interest me as much (like, perhaps,
low bass) and I play a recording that's been made with 48 or more
tracks and a forest of microphones, then I'm not going to enjoy that
recording because it has no image. OTOH, if I like well reproduced,
clean treble and have designed my system to highlight that, and I play
a recording that has been made with microphones that are too bright
or a recording where the engineer has toned down the high frequencies
because he doesn't like "sparkling highs" , then that listener is not
going to get optimum sound from either one of those recordings on his
playback system. A speaker system that can give decent reproduction
irrespective of the recording or the recording venue, simply doesn't
exist and it can't exist. Even if one could buy the ultimate,
theoretical ideal of a speaker system, unless that ideal is carried
all the way back to the recording so that all the music one plays on
one's ideal playback system was captured with a theoretically ideal
microphone system and then recorded with totally transparent
electronics to a theoretically perfect recording device, all bets are
off and the system is still going to be fundamentally flawed. The kind
of control that I believe that Mr. Eickmeier is advocating here is
simply impossible because the variables are simply too many.
Audio Empire
May 23, 2012, 6:55:52 AM5/23/12
to
On Tue, 22 May 2012 18:51:10 -0700, Gary Eickmeier wrote
(in article <a22u4e...@mid.individual.net>):
Unless you "frap" the instrument, or record in an anechoic chamber, that's
impossible.
> At the audio club I demonstrated this with the dry, mono recording of the
> human voice outdoors. I transferred it to my laptop and processed it with
> Audition so that it would pan from extreme right to extreme left chennel.
> This was with my experimental speakers that were entered in The Challenge.
> Most audio people would expect such a dry sound to image from one speaker to
> the other and come from the speaker itself when at the channel extremes. So
> to prove my point, I obtained an orange cone from Home Depot so that I could
> place a visual where the audience perceived the sound to be coming from. I
> started the recording at stage right, and when it got to the center I asked
> them where the voice was. I placed the cone as directed until everyone
> agreed. It ended up centered but a foot or two back behind the line of the
> speakers. Same question when it got to stage extreme left. To their surprise
> the voice was coming not from the speaker but from a foot behind the
> speaker - unmistakably. To me, this proves the image shift, which slightly
> defies the precedence principle. But even the textbooks say that if the
> reflection is strong enough there will be an image shift.
That can also be attributed to a frequency suckout in the voice range of the
speakers used. Conversely, a peak in that range would put the voice forward
of the speaker. Another variable would be room acoustics. A subtractive phase
anomaly could move the voice backwards or and additive one could move it
forward .
(in article <a22u4e...@mid.individual.net>):
impossible.
> At the audio club I demonstrated this with the dry, mono recording of the
> human voice outdoors. I transferred it to my laptop and processed it with
> Audition so that it would pan from extreme right to extreme left chennel.
> This was with my experimental speakers that were entered in The Challenge.
> Most audio people would expect such a dry sound to image from one speaker to
> the other and come from the speaker itself when at the channel extremes. So
> to prove my point, I obtained an orange cone from Home Depot so that I could
> place a visual where the audience perceived the sound to be coming from. I
> started the recording at stage right, and when it got to the center I asked
> them where the voice was. I placed the cone as directed until everyone
> agreed. It ended up centered but a foot or two back behind the line of the
> speakers. Same question when it got to stage extreme left. To their surprise
> the voice was coming not from the speaker but from a foot behind the
> speaker - unmistakably. To me, this proves the image shift, which slightly
> defies the precedence principle. But even the textbooks say that if the
> reflection is strong enough there will be an image shift.
speakers used. Conversely, a peak in that range would put the voice forward
of the speaker. Another variable would be room acoustics. A subtractive phase
anomaly could move the voice backwards or and additive one could move it
forward .
>
> This principle can be a very powerful tool in setting up your speaker system
> for imaging, but if done wrong can be a disaster of Consumer Reports vs Bose
> proportions. Bose did not give correct speaker positioning instructions in
> the owner manual for the 901s, inviting disaster with a strongly negative
> directivity speaker (strong reflected portion of its output). CR reported a
> hole in the middle and stretched soloists, as did many audiophiles. If
> correctly placed by accident, they could be impressive, but if you put them
> too close to the walls all of the criticisms rear their ugly heads.
Bose speakers and systems are lousy. Always have been.
> This principle can be a very powerful tool in setting up your speaker system
> for imaging, but if done wrong can be a disaster of Consumer Reports vs Bose
> proportions. Bose did not give correct speaker positioning instructions in
> the owner manual for the 901s, inviting disaster with a strongly negative
> directivity speaker (strong reflected portion of its output). CR reported a
> hole in the middle and stretched soloists, as did many audiophiles. If
> correctly placed by accident, they could be impressive, but if you put them
> too close to the walls all of the criticisms rear their ugly heads.
KH
May 23, 2012, 7:01:02 AM5/23/12
to
On 5/22/2012 4:18 PM, Sebastian Kaliszewski wrote:
> Gary Eickmeier wrote:
> [... large snip ...]
> > Many people, especially audiophiles, have the impression that the
> recording
> > contains a perfect image of the performance as witnessed from the
> best seat
> > in the house.
Really? I don't know anyone that believes that. It's physically
> Gary Eickmeier wrote:
> [... large snip ...]
> > Many people, especially audiophiles, have the impression that the
> recording
> > contains a perfect image of the performance as witnessed from the
> best seat
> > in the house.
impossible with current recording practices.
> > This may be true with binaural,
> > but stereophonic is a very
> > much different process. The problem with the above analogy is that it
> > pictures the sound as having been "witnessed," or recorded, from the
> vantage
> > point of the listener in the room suspended in the middle of the concert
> > hall. This is not the case.
> What is the case is that all we got is just a little part of a
> soundfield sampled at some predetermined points in space, and those
> points and in fact acoustical transformation assigned with all of them
> do differ significantly among different recordings. And anyway, such a
> transformation loses vast majority of the information -- for a start it
> transforms (projects) 3 dimensional data into just single dimension.
directional information is lost. There is no quantitative or
qualitative difference - in the recorded signal - between say a 500hz
75db signal *recorded* from 120⁰ (from any given reference point) and
the same signal recorded from 0⁰ or 180⁰. Note qualification - recorded
signal - obviously there could be level cues resulting from non-linear
microphone responses, but that's irrelevant.
> > What we have done is dispatched the microphones
> > up to the orchestra, recorded the musicians and the soundstage
> surrounding
> > them, and brought back the sound to be played again from entirely
> within our
> > room, not from outside with holes punched in the walls so we can hear
> it.
the world at large is something I've never heard anyone believe in or
allude to. It's a faulty image, one fraught with wave interference
problems if nothing else. My "image" of stereo is creating a realistic,
continuous sound image exactly analogous to a live venue. Never totally
achieved, but pretty close at times.
<snip>
>
> > I believe that this is for the better, because once
> > we reconstruct the sound fields in the playhback room, all of the
> > characteristics of live sound can be present, making the sound real
> and not
> > a trick.
>
> One litlle problem -- it might well be physically impossible.
I'd say it's certainly impossible as a practical matter.
> > I believe that this is for the better, because once
> > we reconstruct the sound fields in the playhback room, all of the
> > characteristics of live sound can be present, making the sound real
> and not
> > a trick.
>
> One litlle problem -- it might well be physically impossible.
>
> > The stereophonic recording can be thought of as a concentrate, to
> > be mixed with the playback acoustic in a way that models the
> reproduction
> > after the real thing.
information required to create a 3-D sound field. It's gone. You can
certainly use reflected sound to try and capture some sense of
spaciousness, but it cannot be accurate since the you cannot parse the
part of the recording resulting from reflected sound from that resulting
from direct sound. If you could, you still would be screwing up the
directional clues because you cannot recreate the same incident angles
and delay times experienced in the venue.
<snip>
> > Although we must inevitably hear some of the
> > listeining room along with the "flavor" of the recorded acoustic, the
> > realism can be stunning.
You have to hear primarily the listening room, by definition, since
> > listeining room along with the "flavor" of the recorded acoustic, the
> > realism can be stunning.
you're using that room to create the reflections. That's one of the
rubs. You're reflecting both the originally direct sound, and the
originally reflected sound. That can't be accurate. Speaker placement
isn't going to be able to create information that just isn't in the
recording. The "sound field" created by your approach is no less a
contrived illusion than are the many other approaches taken by more
conventional designers and engineers.
Can that seem more realistic despite being totally inaccurate?
Probably, in some instances, with some recordings, in some rooms, to
some listeners. I've heard a number of dipole speakers, in numerous
configurations, and a number of setups over the years with 901's, and
while you can certainly achieve a degree of spaciousness with reflected
sound, I've yet to hear any such systems that sounded more "real" to me
than more conventional speakers, properly set up. In fact, the best
system with 901's I have ever heard was way back in the day, using Mac
gear with 901's mounted on stands. Those stands, however, were JBL
L-100's. Not exactly in keeping with your theory, but capable of
surprising realism at times.
> But what's the basis of your claim. I read your white paper and what you
> wrote here and probably some time ago stumbled upon something from you
> on some audio forum(s)). What I miss is that actual theory you're
> talking about. You describe how thing should be without showing how to
> reach tha goal nor even presenting any argument that this goal is
> acheivable at all.
> Your ideas about speaker directivity and placement such reflected images
> extend the audio scene in a room which is typically (much) smaller than
> recorded performance venue are all interesting but they do not for a
> theory. They are yet another trick withing a big bag of tricks already
> known.
approach either with the exception of a false dichotomy - i.e. there's
the *right* way (Gary's way) and myriad *wrong* ways to create realism.
From the test paper referenced, I see a set of criteria that represent
the testers' opinion of what aspects are important for realism. One
thing I see missing is a simple "which is more realistic" question as a
control for the evaluation criteria chosen. It may well be that any
given listener might rate, for e.g. the Orion as better than the
reference in 4 categories, and equal in two, and still feel the
reference was subjectively more realistic (i.e. any given evaluator may
have significantly different key parameters that signal "realism" to
them than those posed by the test questions).
Having heard neither the Behringers nor the Orions (and obviously not
Gary's brew), I can't comment on the appropriateness of the test
speakers other than to say I have serious doubts about comparison of
sub/satellite systems - relative to bass reproduction - to the Orions.
Using the subs with the Orions, with level matching, would seem more
appropriate.
Keith
Sebastian Kaliszewski
May 23, 2012, 8:07:02 PM5/23/12
to
First It's wihin error circle from the speaker anyway (our senses are not that
precise). Second it has all the drawbacks of sigthte evaluations). Third while
effect could be real afrer all, its cause could be completely different, as
Audio Empire pointed out
> Draw an image model of the problem and you can see easily what is happening.
your apriori assumption how things works, but it lacks any physical or
psychoacoustical explanation. Nice simple drawings are not an explanation.
> Move the speakers closer to the front wall and depth diminishes because the
> reflected image speaker gets closer to the actual one. Move the speakers
> wider, and the total image (or soundstage) becomes narrower! Place them
> within a foot or two of the corners, and you get a "clustering" of acoustic
> images that causes this hole in the middle and six foot wide soloists. I
> threw caution to the winds one fine day and pulled my speakers out from the
> walls and in to about 1/4 of the room width, and all of a sudden the sound
> focused itself like a camera lens and there in front of me was the answer to
> many questions.
response due to particular cancellation and reinforcement caused by room modes,
etc.? How about that depth increase/reduction has nothing to do with simple
geometrical reflections but due to particular changes in ratio between direct
and reverberant sound?
Usable theory must explain things, should also describe limitations of it's
applicability.
Without that it's not a theory, its just a trick recipe.
> I don't know where Andrew got the impression that I disagreed with Floyd on
> something. What I said was that I read all through his book for the answers
> to Linkwitz's very basic questions but couldn't find specific
> recommendations on radiation pattern, speaker positioning or room acoustics
> except to the extent that he agreed that reflected sound was necessary in
> any audio setup. In fact, I wrote to him several times and asked him
> directly about these questions, and also noted the many areas in his book
> that supported my IMT. I was hoping for some sort of endorsement of my
> writings, but it was not forthcoming. I have found that the well-known and
> respected engineers will not commit themselves on paper to any outside
> unsolicited ideas, especially off the beaten path ones like mine. I had a
> nice, long talk on the phone with Siegfried, but he would not write that my
> ideas were answers to his questions.
>
> Same with Dr. Bose, in case you were wondering. I have tried to get him to
> come out with an advanced, audiophile class 901 speaker with a slightly
> different radiation pattern, but he is more interested in the mass market
> than the small group that classifies themselves as audiophiles. And of
> course it is the same as with unsolicited manuscripts sent to Hollywood
> producers - they will not even be opened or acknowledged, for fear of
> lawsuits if they use any of your material without paying you.
>
> So I remain a voice crying in the wilderness. So fine.
experiments (the ones you described above were certainly not well controlled).
If you look at Siegfried Linkwitz page you'll see a lot of physical
explanations, you'll see real hard numbers, you'll see references to
psychoacustcs, etc. For example. when SL tell us that his Plutos should be
listened at closer distance than his Orions (in a same given room), then it's
explained why and supported by hard physics.
Audio Empire
May 23, 2012, 8:15:00 PM5/23/12
to
On Wed, 23 May 2012 04:01:02 -0700, KH wrote
(in article <a23ube...@mid.individual.net>):
> On 5/22/2012 4:18 PM, Sebastian Kaliszewski wrote:
>> Gary Eickmeier wrote:
>> [... large snip ...]
>>> Many people, especially audiophiles, have the impression that the recording
>>> contains a perfect image of the performance as witnessed from the best seat
>>> in the house.
> Really? I don't know anyone that believes that. It's physically
> impossible with current recording practices.
Amen. I think most audiophiles realize that there are so many different ways
to capture a musical performance, that they can't all be optimum. In fact, if
a perfect image of a performance is the goal, then most microphone setups are
just plain wrong.
>>> This may be true with binaural,
>
> I fail to see how it could.
Since a good binaural setup has a pair of high-quality omnidirectional mikes
mounted in a dummy head which has been designed to mimic the dimensions and
the acoustical properties of a skin-covered human head, it probably comes
closer to the ideal capture medium than any other microphone technique.
However, binaural playback only works through headphones, and the quality of
the playback depends, in large measure, on the quality of the headphones.
Even so, binaural recordings cannot differentiate between sounds coming from
directly in front of the dummy head or directly behind. A simple experiment
using a binaural setup will prove this point. While recording, walk around
the dummy head jingling a set of keys. Play the recording back through
headphones. images from the sides appear as they should (often with shocking
realism, especially if one is not used to the effect), but when the keys move
to the front or back of the head, they sound as if they are IN the listener's
head rather than in front or in back. Our ears don't have this problem and
humans can easily tell the direction from which a sound emanates,
irrespective of its direction.
>>> but stereophonic is a very
>>> much different process. The problem with the above analogy is that it
>>> pictures the sound as having been "witnessed," or recorded, from the vantage
>>> point of the listener in the room suspended in the middle of the concert
>>> hall. This is not the case.
>
> Which would be ideal, but again, not practical.
>
>
>> What is the case is that all we got is just a little part of a
>> soundfield sampled at some predetermined points in space, and those
>> points and in fact acoustical transformation assigned with all of them
>> do differ significantly among different recordings. And anyway, such a
>> transformation loses vast majority of the information -- for a start it
>> transforms (projects) 3 dimensional data into just single dimension.
>
> Exactly. With the exception of temporal and magnitude clues, all
> directional information is lost. There is no quantitative or
> qualitative difference - in the recorded signal - between say a 500hz
> 75db signal *recorded* from 120 (from any given reference point) and
> the same signal recorded from 0 or 180. Note qualification - recorded
relationship to the sound source - and then only in the most fundamental way
(it assumes very directional speakers with no back-wave). It cannot be used
to describe the recorded performance's relationship with the listening room
at all.
> <snip>
>>
>>> I believe that this is for the better, because once
>>> we reconstruct the sound fields in the playhback room, all of the
>>> characteristics of live sound can be present, making the sound real and not
>>> a trick.
>>
>> One litlle problem -- it might well be physically impossible.
>
> I'd say it's certainly impossible as a practical matter.
>
>>
>>> The stereophonic recording can be thought of as a concentrate, to
>>> be mixed with the playback acoustic in a way that models the reproduction
>>> after the real thing.
>
> The problem is that the stereophonic recording doesn't have the
> information required to create a 3-D sound field. It's gone. You can
> certainly use reflected sound to try and capture some sense of
> spaciousness, but it cannot be accurate since the you cannot parse the
> part of the recording resulting from reflected sound from that resulting
> from direct sound. If you could, you still would be screwing up the
> directional clues because you cannot recreate the same incident angles
> and delay times experienced in the venue.
Yep.
> <snip>
>>> Although we must inevitably hear some of the
>>> listeining room along with the "flavor" of the recorded acoustic, the
>>> realism can be stunning.
>
> You have to hear primarily the listening room, by definition, since
> you're using that room to create the reflections. That's one of the
> rubs. You're reflecting both the originally direct sound, and the
> originally reflected sound. That can't be accurate. Speaker placement
> isn't going to be able to create information that just isn't in the
> recording. The "sound field" created by your approach is no less a
> contrived illusion than are the many other approaches taken by more
> conventional designers and engineers.
Very true.
(in article <a23ube...@mid.individual.net>):
> On 5/22/2012 4:18 PM, Sebastian Kaliszewski wrote:
>> Gary Eickmeier wrote:
>> [... large snip ...]
>>> Many people, especially audiophiles, have the impression that the recording
>>> contains a perfect image of the performance as witnessed from the best seat
>>> in the house.
> Really? I don't know anyone that believes that. It's physically
> impossible with current recording practices.
to capture a musical performance, that they can't all be optimum. In fact, if
a perfect image of a performance is the goal, then most microphone setups are
just plain wrong.
>>> This may be true with binaural,
>
> I fail to see how it could.
mounted in a dummy head which has been designed to mimic the dimensions and
the acoustical properties of a skin-covered human head, it probably comes
closer to the ideal capture medium than any other microphone technique.
However, binaural playback only works through headphones, and the quality of
the playback depends, in large measure, on the quality of the headphones.
Even so, binaural recordings cannot differentiate between sounds coming from
directly in front of the dummy head or directly behind. A simple experiment
using a binaural setup will prove this point. While recording, walk around
the dummy head jingling a set of keys. Play the recording back through
headphones. images from the sides appear as they should (often with shocking
realism, especially if one is not used to the effect), but when the keys move
to the front or back of the head, they sound as if they are IN the listener's
head rather than in front or in back. Our ears don't have this problem and
humans can easily tell the direction from which a sound emanates,
irrespective of its direction.
>>> but stereophonic is a very
>>> much different process. The problem with the above analogy is that it
>>> pictures the sound as having been "witnessed," or recorded, from the vantage
>>> point of the listener in the room suspended in the middle of the concert
>>> hall. This is not the case.
>
> Which would be ideal, but again, not practical.
>
>
>> What is the case is that all we got is just a little part of a
>> soundfield sampled at some predetermined points in space, and those
>> points and in fact acoustical transformation assigned with all of them
>> do differ significantly among different recordings. And anyway, such a
>> transformation loses vast majority of the information -- for a start it
>> transforms (projects) 3 dimensional data into just single dimension.
>
> Exactly. With the exception of temporal and magnitude clues, all
> directional information is lost. There is no quantitative or
> qualitative difference - in the recorded signal - between say a 500hz
> 75db signal *recorded* from 120 (from any given reference point) and
> signal - obviously there could be level cues resulting from non-linear
> microphone responses, but that's irrelevant.
>
>>> What we have done is dispatched the microphones
>>> up to the orchestra, recorded the musicians and the soundstage surrounding
>>> them, and brought back the sound to be played again from entirely within our
>>> room, not from outside with holes punched in the walls so we can hear it.
>
> This "holes punched in the walls" theory you seem to want to ascribe to
> the world at large is something I've never heard anyone believe in or
> allude to. It's a faulty image, one fraught with wave interference
> problems if nothing else. My "image" of stereo is creating a realistic,
> continuous sound image exactly analogous to a live venue. Never totally
> achieved, but pretty close at times.
The "windows on a performance" analogy works only to explain the listener='s
> microphone responses, but that's irrelevant.
>
>>> What we have done is dispatched the microphones
>>> up to the orchestra, recorded the musicians and the soundstage surrounding
>>> them, and brought back the sound to be played again from entirely within our
>>> room, not from outside with holes punched in the walls so we can hear it.
>
> This "holes punched in the walls" theory you seem to want to ascribe to
> the world at large is something I've never heard anyone believe in or
> allude to. It's a faulty image, one fraught with wave interference
> problems if nothing else. My "image" of stereo is creating a realistic,
> continuous sound image exactly analogous to a live venue. Never totally
> achieved, but pretty close at times.
relationship to the sound source - and then only in the most fundamental way
(it assumes very directional speakers with no back-wave). It cannot be used
to describe the recorded performance's relationship with the listening room
at all.
> <snip>
>>
>>> I believe that this is for the better, because once
>>> we reconstruct the sound fields in the playhback room, all of the
>>> characteristics of live sound can be present, making the sound real and not
>>> a trick.
>>
>> One litlle problem -- it might well be physically impossible.
>
> I'd say it's certainly impossible as a practical matter.
>
>>
>>> The stereophonic recording can be thought of as a concentrate, to
>>> be mixed with the playback acoustic in a way that models the reproduction
>>> after the real thing.
>
> The problem is that the stereophonic recording doesn't have the
> information required to create a 3-D sound field. It's gone. You can
> certainly use reflected sound to try and capture some sense of
> spaciousness, but it cannot be accurate since the you cannot parse the
> part of the recording resulting from reflected sound from that resulting
> from direct sound. If you could, you still would be screwing up the
> directional clues because you cannot recreate the same incident angles
> and delay times experienced in the venue.
> <snip>
>>> Although we must inevitably hear some of the
>>> listeining room along with the "flavor" of the recorded acoustic, the
>>> realism can be stunning.
>
> You have to hear primarily the listening room, by definition, since
> you're using that room to create the reflections. That's one of the
> rubs. You're reflecting both the originally direct sound, and the
> originally reflected sound. That can't be accurate. Speaker placement
> isn't going to be able to create information that just isn't in the
> recording. The "sound field" created by your approach is no less a
> contrived illusion than are the many other approaches taken by more
> conventional designers and engineers.
KH
May 24, 2012, 9:09:23 AM5/24/12
to
On 5/23/2012 5:15 PM, Audio Empire wrote:
> On Wed, 23 May 2012 04:01:02 -0700, KH wrote
> (in article<a23ube...@mid.individual.net>):
><snip>
> On Wed, 23 May 2012 04:01:02 -0700, KH wrote
> (in article<a23ube...@mid.individual.net>):
>>>> This may be true with binaural,
>>
>> I fail to see how it could.
>
> Since a good binaural setup has a pair of high-quality omnidirectional mikes
> mounted in a dummy head which has been designed to mimic the dimensions and
> the acoustical properties of a skin-covered human head, it probably comes
> closer to the ideal capture medium than any other microphone technique.
> However, binaural playback only works through headphones, and the quality of
> the playback depends, in large measure, on the quality of the headphones.
>
> Even so, binaural recordings cannot differentiate between sounds coming from
> directly in front of the dummy head or directly behind.
That's pretty much my point. You can come closer, but still no cigar.
>>
>> I fail to see how it could.
>
> Since a good binaural setup has a pair of high-quality omnidirectional mikes
> mounted in a dummy head which has been designed to mimic the dimensions and
> the acoustical properties of a skin-covered human head, it probably comes
> closer to the ideal capture medium than any other microphone technique.
> However, binaural playback only works through headphones, and the quality of
> the playback depends, in large measure, on the quality of the headphones.
>
> Even so, binaural recordings cannot differentiate between sounds coming from
> directly in front of the dummy head or directly behind.
<snip>
>> This "holes punched in the walls" theory you seem to want to ascribe to
>> the world at large is something I've never heard anyone believe in or
>> allude to. It's a faulty image, one fraught with wave interference
>> problems if nothing else. My "image" of stereo is creating a realistic,
>> continuous sound image exactly analogous to a live venue. Never totally
>> achieved, but pretty close at times.
>
> The "windows on a performance" analogy works only to explain the listener='s
> relationship to the sound source - and then only in the most fundamental way
> (it assumes very directional speakers with no back-wave). It cannot be used
> to describe the recorded performance's relationship with the listening room
> at all.
And pitiful speakers those would be indeed. I think one misconception
>> the world at large is something I've never heard anyone believe in or
>> allude to. It's a faulty image, one fraught with wave interference
>> problems if nothing else. My "image" of stereo is creating a realistic,
>> continuous sound image exactly analogous to a live venue. Never totally
>> achieved, but pretty close at times.
>
> The "windows on a performance" analogy works only to explain the listener='s
> relationship to the sound source - and then only in the most fundamental way
> (it assumes very directional speakers with no back-wave). It cannot be used
> to describe the recorded performance's relationship with the listening room
> at all.
that Gary exhibits is a belief that there *is* some point or
presentation that would be universally agreed upon as "most realistic".
To a large extent that, as you've alluded to in this thread already,
is largely a matter of preference (whether image size, pinpoint imaging,
etc.) depending upon, in large part, the factors each individual
listener finds most central to the illusion. The fact that there are
various audiophile groups that, respectively, find box, horn, dipole,
and omnidirectional (e.g. MBL's - for the rich) to be most realistic
would tend to support that conclusion rather well IMO.
I think if we were to generalize anything to "all" audiophiles, it would
be that *they* recognize that the recording is the first, and most
fundamentally challenging part of the whole process. It is clear, to
most IMO, that the effectiveness of anything done on the playback side
of the process, no matter how innovative, or clever, will always be
limited by the information contained in the recorded signal.
Keith
Randy Yates
May 24, 2012, 1:46:32 PM5/24/12
to
Audio Empire <audio_...@comcast.net> writes:
> [...]
simply play back a binaural recording using earphones but must equalize
for this resonance as well.
--
Randy Yates
Digital Signal Labs
http://www.digitalsignallabs.com
> [...]
> Since a good binaural setup has a pair of high-quality omnidirectional mikes
> mounted in a dummy head which has been designed to mimic the dimensions and
> the acoustical properties of a skin-covered human head, it probably comes
> closer to the ideal capture medium than any other microphone technique.
> However, binaural playback only works through headphones, and the quality of
> the playback depends, in large measure, on the quality of the headphones.
>
> Even so, binaural recordings cannot differentiate between sounds coming from
> directly in front of the dummy head or directly behind. A simple experiment
> using a binaural setup will prove this point. While recording, walk around
> the dummy head jingling a set of keys. Play the recording back through
> headphones. images from the sides appear as they should (often with shocking
> realism, especially if one is not used to the effect), but when the keys move
> to the front or back of the head, they sound as if they are IN the listener's
> head rather than in front or in back. Our ears don't have this problem and
> humans can easily tell the direction from which a sound emanates,
> irrespective of its direction.
This may be due to the concha resonance. As I understand it, one cannot
> mounted in a dummy head which has been designed to mimic the dimensions and
> the acoustical properties of a skin-covered human head, it probably comes
> closer to the ideal capture medium than any other microphone technique.
> However, binaural playback only works through headphones, and the quality of
> the playback depends, in large measure, on the quality of the headphones.
>
> Even so, binaural recordings cannot differentiate between sounds coming from
> directly in front of the dummy head or directly behind. A simple experiment
> using a binaural setup will prove this point. While recording, walk around
> the dummy head jingling a set of keys. Play the recording back through
> headphones. images from the sides appear as they should (often with shocking
> realism, especially if one is not used to the effect), but when the keys move
> to the front or back of the head, they sound as if they are IN the listener's
> head rather than in front or in back. Our ears don't have this problem and
> humans can easily tell the direction from which a sound emanates,
> irrespective of its direction.
simply play back a binaural recording using earphones but must equalize
for this resonance as well.
--
Randy Yates
Digital Signal Labs
http://www.digitalsignallabs.com
Audio Empire
May 24, 2012, 8:21:45 PM5/24/12
to
On Thu, 24 May 2012 10:46:32 -0700, Randy Yates wrote
(in article <a27afn...@mid.individual.net>):
You may have a point there. If so, that's a big flaw in binaural recording. I
can't imagine that equalizing for this resonance would be easy to do without
extensive auditory measurements being made.
(in article <a27afn...@mid.individual.net>):
can't imagine that equalizing for this resonance would be easy to do without
extensive auditory measurements being made.
Arny Krueger
May 25, 2012, 8:53:24 AM5/25/12
to
"Audio Empire" <audio_...@comcast.net> wrote in message
news:jpmja...@news1.newsguy.com...
listening. The most impressive demo I've participated in involved a
portable binaural recording system disguised as eyeglasses with real time
monitoring.
>> This may be due to the concha resonance. As I understand it, one cannot
>> simply play back a binaural recording using earphones but must equalize
>> for this resonance as well.
> You may have a point there. If so, that's a big flaw in binaural
> recording. I
> can't imagine that equalizing for this resonance would be easy to do
> without
> extensive auditory measurements being made.
subjectively, any such resonances are dealt with automagically. Of course
you need a competent equalizer - a 4 to 6 band full parametric would be my
tool of choice. Unfortunately I know of no portable digital players with
this feature - most top out with 5 band graphic equalizers which are
amazingly blunt sticks for actually doing things well.
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