Greatest improvements to hi fi
MYKEY
EQ: The right EQ can make any speaker sound better in any room. It is true
that your room should have a combination of hard and soft surfaces that
do not create standing waves. I suggest you use 31 band third octive EQ
and adjust for cut only. The better EQs build today are fantastic!
You say that Im creating "phase errors" with my EQ,but I need to break the
news to you: any recording you play is loaded with phase errors from the
microphone all the way to the printing press. Im using my EQ to tune out
some of those phase errors, and compensate to the room.
Electronic Crossover: separate and amplify sub low mids highs according to
your own taste. control the volume and crossover points of each frequency
band. You are no longer stuck with the sound of your speakers,you can tune
it for your own ears pleasure. The new xovers include digital delays to
align phase of speaker elements, and it really works.
Sub woofer: Any system will benefit by adding sub sonic reproduction,
especially at low volumes. Even small systems. Even in your car.
This is not for rap music only, classical listener will be very pleased
with a new sub woofer.
I think (suggest) big subwoofers sound better. There is no way to make
a little speaker work like a big one, even by porting and folding the
cabinet design. The small subs have a big hump in the frequency response
(lower mid range hump) and dont even touch subsonic.
Cossie
news:c3l7l...@enews4.newsguy.com...
> Here are the 3 greatest improvements to hi fi, despite what you have been
told:
>
> EQ: The right EQ can make any speaker sound better in any room. It is
true
> that your room should have a combination of hard and soft surfaces that
> do not create standing waves. I suggest you use 31 band third octive EQ
> and adjust for cut only. The better EQs build today are fantastic!
>
31 band eq units are great for sound reinforcement situations where you need
to grab a problem frequency quickly, but for hi fi (or any other permanent
installation)you should really use a good parametric eq that allows you to
more specifically choose the proper frequency as well as the bandwidth of
the cut or boost you are applying.
Bill Balmer
neo...@webtv.net
has heard a lot of equipment in the past allow me to ask the following:
do these crossovers allow the frequencies to be routed to the mid from
the tweeter and the mid to the woofer? This is what the KLH 12s did and
I always had them set at the max downward. Are there time delays in
modern amps/receivers for four speaker set ups? I`ve heard something
about this in home theater systems , how about straight audio systems?
Subs help but are small improvments compared to time delays.
Rich Andrews.
news:c3l7l...@enews4.newsguy.com:
> Here are the 3 greatest improvements to hi fi, despite what you have
been told:
>
> EQ: The right EQ can make any speaker sound better in any room. It is
true
> that your room should have a combination of hard and soft surfaces
that
> do not create standing waves. I suggest you use 31 band third octive
EQ
> and adjust for cut only. The better EQs build today are fantastic!
I think a 31 band eq is overkill. If the speakers are reasonably flat and
the room not too bad, then a 7-10 band parametric eq would suffice.
Changing the acoustic characteristics of a room is the easiest way to
improve upon a sound system. The creation of LF standing waves is
something that is hard to avoid. One can control standing waves with the
addition of a parametric EQ. Reflections can be controlled with wall
hangings, drapes, etc.
>
> You say that Im creating "phase errors" with my EQ,but I need to break
the
> news to you: any recording you play is loaded with phase errors from
the
> microphone all the way to the printing press. Im using my EQ to tune
out
> some of those phase errors, and compensate to the room.
Care to elaborate how you are using your frequency EQ as a phase EQ?
>
> Electronic Crossover: separate and amplify sub low mids highs
according to
> your own taste. control the volume and crossover points of each
frequency
> band. You are no longer stuck with the sound of your speakers,you can
tune
> it for your own ears pleasure. The new xovers include digital delays
to
> align phase of speaker elements, and it really works.
Messing with a crossover is something that is part science, part art, and
part black magic. I wouldn't mess with the crossovers in my speakers for
all the tea in China. All I would do is make the speakers sound bad.
YMMV, however but if one has excellent speakers, then the crossover would
be the last place I would look.
>
> Sub woofer: Any system will benefit by adding sub sonic reproduction,
> especially at low volumes. Even small systems. Even in your car.
> This is not for rap music only, classical listener will be very
pleased
> with a new sub woofer.
>
I diagree. My speakers are flat to 20 hz without a sub, so I see no
reason to add one. All it will do is add distortion and change the
frequency response to be something other than flat. I am sure that there
are other people who have speakers flat to 20hz.
> I think (suggest) big subwoofers sound better. There is no way to make
> a little speaker work like a big one, even by porting and folding the
> cabinet design. The small subs have a big hump in the frequency
response
> (lower mid range hump) and dont even touch subsonic.
A bad bass speaker is a bad bass speaker. Physics generally dictates that
to move a fair amount of air requires a large diaghragm. Physics also
dictates that a large speaker system will have some significant advantages
over small speaker systems particularly if multiple drivers are involved.
The 3 greatest things that has happened to audio in the last couple of
decades are:
1) Digital audio, aka the CD/DVD/SACD.
2) Low distortion speakers like the ones at:
http://www.d-s-t.com/peerless/dataover/wo_sls.htm
3) The low noise, low distortion op-amp and DAC/ADC.
r
--
Nothing beats the bandwidth of a station wagon filled with DLT tapes.
chung
I am too lazy to come up with three, but I know what is number 1:
Digital Audio. This includes the discovery of the sampling theorem,
development of PCM hardware and software, advances in memory technology
(for instance the CD and the DVD) that allows digital representation of
performances, whether good or bad, to be preserved indefinitely without
degradation, digital filter technology, integrated circuit advances, and
dither techniques.
Everything else seems like a distant second at best.
I guess some may consider this list bigger than just one item. And of
course, vinylphiles may not agree :).
Tip
> Here are the 3 greatest improvements to hi fi,
despite what you have been told:
> EQ
> Electronic Crossover
> Sub woofer
I agree. Are you familiar with the Tact Audio line of
components (www.tactaudio.com)? I'm doing all of the
above with the Tact RCS 2.2X digital EQ and XO, S2150
amps (which also can do digital EQ and XO), and W410
subwoofers. It has made a huge improvement over my
previous system. There are several new systems about
to come into the market (e.g., NHT) that utilize these
"improvements".
> I think (suggest) big subwoofers sound better.
There is no way to make
> a little speaker work like a big one...
I think his is because a small woofer in a subwoofer
must have a long excursion which is a source of
distortion. But a large woofer with short excursion is
too massive to react quickly and is hard to integrate
with the main speakers. A subwoofer with multiple
small woofers (10") with short excursions seems to be
the best for integration with the main speakers and
allows a higher crossover point.
Regards,
Tip
Kalman Rubinson
>As someone who does not keep up with delvelopments in the industry, but
>has heard a lot of equipment in the past allow me to ask the following:
>do these crossovers allow the frequencies to be routed to the mid from
>the tweeter and the mid to the woofer? This is what the KLH 12s did and
>I always had them set at the max downward.
That's what a 3way crossover does. The more flexible, the better.
> Are there time delays in
>modern amps/receivers for four speaker set ups?
Again, the better ones do.
Kal
Dick Pierce
> Here are the 3 greatest improvements to hi fi, despite what you have been told:
>
> EQ: The right EQ can make any speaker sound better in any room. It is true
> that your room should have a combination of hard and soft surfaces that
> do not create standing waves. I suggest you use 31 band third octive EQ
> and adjust for cut only. The better EQs build today are fantastic!
>
> You say that Im creating "phase errors" with my EQ,but I need to break the
> news to you: any recording you play is loaded with phase errors from the
> microphone all the way to the printing press. Im using my EQ to tune out
> some of those phase errors, and compensate to the room.
Well, I'm NOT going to be one of the ones say you create "phese errors."
I AM going to be one of the ones telling you that you are ignoring the
simple and inevitable physical fact that you CANNOT correct non-minimum
phase response issues with a minimum-phase correction. That's a whole
different ball of wax. Without going into the nitty details of why this
is so, let's explore one manifestation of the problem and show why your
EQ solution simply doesn't work as neatly as you think.
Many room problems, for example, those that show an excessively high-Q
resonance at certain frequencies (call it "boominess") result in an
anomolously and excessively long reverberation time at that frequency.
CHanging the amount of energy you put into that frequency DOES NOT
AND CANNOT change the reverberation time, indeed, the Q of the resonance
at that frequency.
In attempting to correct for the resulting anomolous bump in the steady-
state frequency response at that frequency by putting a severe notch in
at that frequency, you find that first, you have seriously screwed up
the first-arrival response of the signal and second, that the steady
state response has not changed that much.
The way to fix room problems is to fix the room.
> Electronic Crossover: separate and amplify sub low mids highs according to
> your own taste. control the volume and crossover points of each frequency
> band. You are no longer stuck with the sound of your speakers,you can tune
> it for your own ears pleasure. The new xovers include digital delays to
> align phase of speaker elements, and it really works.
Well, no. Assume, for the moment, that the person who designed the
speakers to begin with understood the complex technical issues involved
in the design of the system. That would mean, for example, that the
original integrated crossover was designed to include compensation for
the non-ideal response of the system, and may well have incorporated
delay issue into the design.
Now, you're proposing to essentially throw all that away and, with NO
knowledge of the driver's characteristics, no knowledge of the actual
implementational details of the design goals, with NO means of reason-
ably obtaining dependable information about how changes in crossover
response will affect the system response, throw out all that hard work
that specifically tuned a carefully chosen set of components that are
designed to work TOGETHER as a SYSTEM and replace it with some generic
off-the-shelf "solution" that has no means of providing the same level
of fine tuning.
Designing a crossover DOES NOT just involve selecting the crossover
frequency and gain, it also involves tuning the frequency response
of each of the pass bands to suit the specifica requiremements of the
individual drivers used, something generic electronic croccovers
are simply not capable of doing.
> I think (suggest) big subwoofers sound better. There is no way to make
> a little speaker work like a big one, even by porting and folding the
> cabinet design. The small subs have a big hump in the frequency response
> (lower mid range hump) and dont even touch subsonic.
In a word, this suggestion is simply wrong. The relationship between
cabinet size, system response and efficiency is an equation that allows
adjusting any one of these degrees of freedom to obtain the desired
combination of the other. The relationship looks like:
n0 = kn Vb F3^3
where n0 is the reference efficiency of the system, kn is the system
response constant, Vb is the enclosure volume and F3^3 is the low-
frequency cutoff of the system.
Now, YOUR assertion is that small enclosure have "a big hump in the
frequency response and don't even touch subsomic." That assertion is
simply NOT sup[ported or even supportable by the actual physics
involved. Indeed, it iw quite possible for the response constant
kn to remain the same and simply exchange enclosure size for efficiency
to obtain the same response to the same cutoff frequency.
Now, it is easily possible to build a small subwoofer that behaves as
you suggest, just as it is possible to screw up any other engineering
task.
But engineering incompetence, unfortunately rampant in the audio
industry, is not PROOF of inherent physical behavior.
Stig Erik Tangen
> Here are the 3 greatest improvements to hi fi, despite what you have been told:
I do agree that this is important, but there is one thing that is even
more so - room acoustics treatment. A properly designed room is in my
opinion the most important part in any audio system.
Stig Erik Tangen
Stig Erik Tangen
> The way to fix room problems is to fix the room.
I couldnt agree more! Fixing time-domain problems by changing the signal
amplitude simply cant work, and I dont understand why some still try to
do this.
I do have a great room, and know the importance of having such a room.
However, with EQ you can tailor the speaker's bass response to your room
and to your spesific setup. Most speakers are placed away from the
walls, and you will get peaks and dips because of this non-linear
acoustic loading, as well as from the boundary reflections. You should
of course first find a placement of both speakers and listening position
that gives the flattest possible response, but even so its really hard
to get a ruler-flat response below 200 Hz. EQ *can* fix this, because
its not a time-domain problem.
> Designing a crossover DOES NOT just involve selecting the crossover
> frequency and gain, it also involves tuning the frequency response
> of each of the pass bands to suit the specifica requiremements of the
> individual drivers used, something generic electronic croccovers
> are simply not capable of doing.
Many off the shelf crossovers also have parametric EQ and shelf filters,
so you can actually obtain a flat summed response, provided that you
have measurement equipment... you need to know what you are doing of
course! (sadly, 99,97% of you hi-fi nuts come short here...) If you can
obtain excact the same filter response, I'm sure you will agree that the
active filter have some advantages over the passive filter.
Regards,
Stig Erik Tangen
snapper_...@yahoo.com
>Here are the 3 greatest improvements to hi fi, despite what you have been told:
>
> EQ: The right EQ can make any speaker sound better in any room. It is true
> that your room should have a combination of hard and soft surfaces that
> do not create standing waves. I suggest you use 31 band third octive EQ
> and adjust for cut only. The better EQs build today are fantastic!
I'll semi agree with this statement because not everyone has a perfect,
or even a decent room for listening and the trade off between horrid
sound due to poor room conditions vs judicious use of an eq is minor.
However, I am more of a purist and prefer to set up the speakers and
room properly, if possible.
In my modest project studio, a couple of strategically placed Sonex
panels and furniture as well as proper placement of my monitors worked
wonders compared to what it sounded like *bare*.
Snapper
P.S. Sorry, I hit the enter key too soon on the last post :(
MYKEY
A parametric EQ would be a great choice, and takes a liitle practice. Try at
least a three band parametric. There are also paragraphic EQs that have the
best of both worlds. A graphic is not just for stadium sound anymore It will
work great in your living room too!
This type of system connects the output of your conventional stereo preamp
(line level) to the input of the electronic crossover. The crossover
sends line level outputs to individual power amps for low mid high.
You select the frequency band and volume for each speaker component:
10-70hz goes to sub woofer
70- 150 hz goes to woofers
150-2500 hz goes to mid speakers
2500- up goes to tweeter
This is only one example, YOU choose the combination YOU like!
The digital delay corrects the phase lag between speakers, even speakers
in the same cabinet. PERFECT phase alignment is now a reality.
In my living room I am using a five section surround amp to TRIAMP
my speakers. The sub is in mono.
My entire setup was constructed for less than $1000, and BLOWS AWAY systems
costing FIVE TIMES AS MUCH!
ANY speaker system can be adapted to work this way, even bookshelf speakers.
DARE TO EQ!
My next addition? triamped magnapans! not cheap but worth every penny.
Nousaine
wrote:
...snip to content.....
>One can control standing waves with the
>addition of a parametric EQ. Reflections can be controlled with wall
>hangings, drapes, etc.
Parametric EQ can only be partially effective with standing wave issues. They
can ameliorate peaks but aren't useful for compensating nulls.
...snip.....>
I diagree. My speakers are flat to 20 hz without a sub, so I see no
>reason to add one. All it will do is add distortion and change the
>frequency response to be something other than flat. I am sure that there
>are other people who have speakers flat to 20hz.
Not many; practically none at a useful SPL level. Even large floortstanding
models are seldom useful below 30-40 Hz. One reason is that the locations one
would choose for best upper range performance are, by and large, nowhere near
optimal for subwoofer frequencies. (i.e. they will nearly always fail to excite
the width mode in a room rendering a null at typical listening positions
between 35 and 60 Hz.
>> I think (suggest) big subwoofers sound better. There is no way to make
>> a little speaker work like a big one, even by porting and folding the
>> cabinet design. The small subs have a big hump in the frequency
>response
>> (lower mid range hump) and dont even touch subsonic.
Few large ones will do anything of significance below 25 Hz. No commerical
subwoofer has significant SPL capability below 16 Hz (no not even that one that
claims 8 Hz.)
It is common for "subwoofers" to have maximal output capability at 50-60 Hz
with dynamic capability falling at 12-20 dB per octave at lower frerquencies.
For example I just tested a subwoofer that was capable of 112 dB at 62 Hz and
91 dB at 20 Hz with an average SPL capability (10% distortion limit) of 106 dB
from 25 to 62 Hz.
This model thus had usable dynamic capability at 20 Hz but with output that
falls at 10 dB per octave below 62 Hz. It's pretty normal, perhaps even a
little above average for subwoofers. But still better than the majority of
tower speakers.
Sean Fulop
> Digital Audio. This includes the discovery of the sampling theorem,
> development of PCM hardware and software, advances in memory
> technology (for instance the CD and the DVD) that allows digital
> representation of performances, whether good or bad, to be preserved
> indefinitely without degradation, digital filter technology,
> integrated circuit advances, and dither techniques.
>
> Everything else seems like a distant second at best.
>
> I guess some may consider this list bigger than just one item. And of
> course, vinylphiles may not agree :).
No, I think I agree. I'm just bitter about the fact that it's taken
this long for CD-players to become affordable that actually sound
half-decent. My newest one is great. But all the others before
basically were no match for vinyl.
Maybe $5000 players have always sounded totally awesome, but I wouldn't
know. My 20-year old mid-price turntable with a $100 cartridge sounds
twice as good as any moderately priced CD-player from even just a few
years ago. I know because I have one of the best mid-price players from
1997. Better than its predecessors, but still cruddy next to the ol'
Thorens.
-Sean
Sean Fulop
> or even a decent room for listening and the trade off between horrid
> sound due to poor room conditions vs judicious use of an eq is minor.
>
But, you've got to admit, no amount of EQ can turn a farmer's quonset
into a decent-sounding listening environment. Some amount of room
treatment has to be involved in the equation, even if perfection cannot
be achieved.
-Sean
Nousaine
>MYKEY wrote:
>
>> Here are the 3 greatest improvements to hi fi, despite what you have been
>told:
>>
>> EQ: The right EQ can make any speaker sound better in any room. It is true
>> that your room should have a combination of hard and soft surfaces that
>> do not create standing waves.
Standing waves occur between any two parallel surfaces and at low frequencies
are a function of the distances of those surfaces (room dimensions) and not the
absorption characteristics of those surfaces.
>>
>> Sub woofer: Any system will benefit by adding sub sonic reproduction,
>> especially at low volumes. Even small systems. Even in your car.
>> This is not for rap music only, classical listener will be very pleased
>> with a new sub woofer.
This is generally true.
>I am too lazy to come up with three, but I know what is number 1:
>Digital Audio. This includes the discovery of the sampling theorem,
>development of PCM hardware and software, advances in memory technology
>(for instance the CD and the DVD) that allows digital representation of
>performances, whether good or bad, to be preserved indefinitely without
>degradation, digital filter technology, integrated circuit advances, and
>dither techniques.
>
>Everything else seems like a distant second at best.
Here's my list;
negative fedback stabilized amplifiers
moving coil loudspeakers
information theory
solid state
integrated circuits
useful acquisition/storage media (as in tape/digital audio)
All of these were pioneered by the telecommunications industry and eventually
trickled down to consumer audio.
The powered subwoofer and modern digital EQ are but a couple end-user benefits
in the long chain of industrial development that ultimately results in better
sound at home and in the car.
IMO development has progressed so rapidly in the past 25 years that any
reasonably interested enthusiast can now buy a system for 2-3 k that
outperforms anything one could buy for any amount of money in 1975.
I love these threads though. They make me step back from my puny personal
challenges at any given moment and appreciate just how well off I am today.
Stig Erik Tangen
> Standing waves occur between any two parallel surfaces and at low frequencies
> are a function of the distances of those surfaces (room dimensions) and not the
> absorption characteristics of those surfaces.
Standing waves also occur between non-parallel surfaces. If you make a
room completely without parallel surfaces, you will still have standing
waves. The only difference is that the standing wave pattern is a lot
harder to predict.
Stig Erik Tangen
Nousaine
wrote:
This is true. I should have stipulated opposing surfaces. This also points out
that non-parallel walls do not eliminate standing waves, as Urban Legend holds.
snapper_...@yahoo.com
Absolutely, which is why I stated "However, I am more of a purist and
prefer to set up the speakers and room properly, if possible."
IOW I agree with you :)
Using an EQ, IMHO should be as a last resort only and in that case the
positives of using one will far outweigh the negative, which would be
inferior sound.
Most times however, there is a fundamental problem that can be solved by
proper speaker placement or relocation of furniture etc.
One thing that I see is that people often choose the wrong speakers for
the room that they will be listening in.
These may be fine speakers, but are just a poor match for the size and
design of the listening room.
snap
MYKEY
cabinet) say a 15" woofer, it has no problem responding at 10-15 hz
and this is how we check the compliance of the speaker cone for noises.
I know if I put a 15 hz tone into my theater speakers it will be rolled off
but audible. These 15" woofers have no problem moving at 15 hz. And I
also know that by adjustment of EQ and X over I can make it flat to that
15hz.
How low is turntable rumble? 22 hz? 17hz? 15? Many speakers have no trouble
at all reproducing that.(the bigger the better)
The subwoofer is often a subliminal effect that is felt in the chest.
Turn it off and you can really tell it's missing.
Norman Schwartz
news:c3n57...@enews1.newsguy.com...
> mykeym...@yahoo.com (MYKEY) wrote in
> news:c3l7l...@enews4.newsguy.com:
>
> > Here are the 3 greatest improvements to hi fi, despite what you have
> been told:
> >
> > EQ: The right EQ can make any speaker sound better in any room. It is
> true
> > that your room should have a combination of hard and soft surfaces
> that
> > do not create standing waves. I suggest you use 31 band third octive
> EQ
> > and adjust for cut only. The better EQs build today are fantastic!
>
> I think a 31 band eq is overkill. If the speakers are reasonably flat and
> the room not too bad, then a 7-10 band parametric eq would suffice.
> Changing the acoustic characteristics of a room is the easiest way to
> improve upon a sound system.
I have a 1/3 octave EQ (in the closet). I've always seen it said that if you
EQ your room flat, you are going to be unhappy with the resultant sound. It
appears that was my experience as well. Getting neat sound from a 31 band
1/3 octave EQ seems "hit and miss" and quickly becomes a full-time
occupation or obsession. My recommendation is not to even get started.
Nousaine
One thing that gets overlooked in the EQ phase is that response in the far
field should not be equalized to be "flat" except in an octave to octave sense.
A loudspeaker that measures flat in an anechoic chamber or in the near field
will have a downsloping shape when measured in the far field. In a typical room
this will generally be about 1 to 1.5 dB per octave as frequency increases.
Tip
> I have a 1/3 octave EQ (in the closet). I've always
seen it said that if you
> EQ your room flat, you are going to be unhappy with
the resultant sound. It
> appears that was my experience as well.
That's true, you don't actually want a flat response at
the listening position in a room. What you want is
more like the response you would get if you had
flat-response speakers in a "perfect" room. The
frequency graph would have a downward slope from the
low frequencies to the high frequencies, rolling-off at
both ends, and is not necessarily linear. If you
measure your speakers (don't use sine waves) at the
listening position, you will probably see that it
already has this response if you ignore the dips and
peaks caused by the room modes. Use your EQ to
smooth-out the response to the speaker/room's natural
slope above 300-500 Hz, but only attenuate the peaks in
lower frequencies. Do not boost the low frequency dips
by very much because it really doesn't work well for
many reasons, not the least of which is that you may
damage your equipment and speakers. And ignore very
narrow peaks and dips. You can also try moving your
speakers closer to the front wall to increase the room
gain, which then can be attenuated with the EQ. This
method utilizes the room gain instead of amplifier gain
and will be easier on your amplifier and woofers. It
also will produce a more time-coherent low-end response
yielding a tighter bass and greater dynamics.
Regards,
Tip
Tip
> I couldnt agree more! Fixing time-domain problems by
changing the signal
> amplitude simply cant work, and I dont understand why
some still try to
> do this.
Very true. But today we have digital EQ that does fix
time-domain problems in the time-domain (see Tact
Audio's RCS devices).
Regards,
Tip
snapper_...@yahoo.com
> I know if I hook up a sine wave generator and amp to a speaker (even no
> cabinet) say a 15" woofer, it has no problem responding at 10-15 hz
> and this is how we check the compliance of the speaker cone for noises.
Not a good idea to run that low a frequency through a speaker that is
not mounted inside a box, especially if it's a speaker designed for a
sealed acoustic suspension type system. Since there is no air in the box
to dampen the cone excursions you might over extend the travel and break
something.
> I know if I put a 15 hz tone into my theater speakers it will be rolled off
> but audible. These 15" woofers have no problem moving at 15 hz. And I
> also know that by adjustment of EQ and X over I can make it flat to that
> 15hz.
"Flat" as determined by what?
If the speakers were designed to reproduce 15hz you should not have to
eq anything.
IOW they are rolled off for a sound design reason.
Adjusting the Xover is another matter.
Just because you can make the speaker respond at a lower frequency than
it might be designed to do doesn't mean you have flattened the response
of that speaker and made it more natural sounding.
Also the chances are good that you are attempting to use a speaker in a
capacity that it may not be designed for and it's almost a given that
you will be increasing the distortion as well.
Additionally unless you are using a parametric eq that allows you to
adjust the bandwidth and Q chances are that while you are boosting that
15 hz slider up, you are also effecting frequencies well outside that
band.
Speakers are designed by the manufacturer to meet certain specs and for
certain reasons.
If speaker A was designed to have a certain bandwidth the design specs
of the manufacturer should be respected because it was designed that way
for a specific reason.
There is a reason why Speaker A is rated at 40hz-18khz and not 15hz to
40khz.
If the manufacturer could extend the frequency response of Speaker A
like that, his advertising agency could have a field day.
I am talking of high quality speakers of course.
> How low is turntable rumble? 22 hz? 17hz? 15? Many speakers have no trouble
> at all reproducing that.(the bigger the better)
Nothing wrong with a nice steep curve (18db/octave Butterworth) low cut
filter.
There is no sense wasting amplifier power on rumble.
> The subwoofer is often a subliminal effect that is felt in the chest.
> Turn it off and you can really tell it's missing.
True, but again how does this relate to being "flat or natural
sounding"?
Equalizers have their uses but IMHO extending the range of speakers is
not a good application of one and unfortunately this is typically what
they are used for and the reason why most eq's always seem to be set up
in "smiley face" configuration.
A good eq properly set up can be used to minimize small dips and peaks
in room/speaker response when placement can't solve the problem.
Using one as a sort of gigantic tone control is a recipe for disaster
IMHO though even if you can make the walls shake by boosting the lows
12db. You will be boosting out of band frequencies as well and in
addition you might be asking your speaker to do more than it was
designed to do, IOW higher distortion.
Tip
> I diagree. My speakers are flat to 20 hz without a
sub, so I see no
> reason to add one. All it will do is add distortion
and change the
> frequency response to be something other than flat.
I am sure that there
> are other people who have speakers flat to 20hz.
That's what I used to think also. I have B&W801s,
which aren't particularly bass-shy, and was convinced I
didn't need a subwoofer. Now I have stereo subwoofers!
It really can make a huge difference even with
full-range speakers. Plus you can place the subwoofers
and your main speakers where each produces the best
sound for the frequency range they are reproducing,
especially if multiple subs are used. It does require
the proper crossover electronics with time delay
capabilities for seamless integration.
Regards,
Tip
Stewart Pinkerton
> I know if I put a 15 hz tone into my theater speakers it will be rolled off
> but audible. These 15" woofers have no problem moving at 15 hz.
Unfortunately, the threshold of hearing at 15Hz is more than 100dB SPL
(assuming you believe that anything below 20Hz is audible at all), so
I seriously doubt that you can hear those speakers *at 15Hz*. You will
of course be generating large amounts of 2nd and 3rd harmonic
distortion, and you can certainly hear 45Hz at 90dB or less.
> And I
> also know that by adjustment of EQ and X over I can make it flat to that
> 15hz.
Only at very low SPLs, since the limit below 30-40Hz will be set by
the Xmax of the speaker, which is *not* susceptible to EQ. IOW, a
normal 15" driver not specifically designed for the ultra long throw
needed for subwoofer use, simply can *not* move enough air to even be
*audible* at 20Hz. I canna' change the laws o' physics, cap'n.....
> How low is turntable rumble? 22 hz? 17hz? 15? Many speakers have no trouble
> at all reproducing that.(the bigger the better)
Who cares about obsolete technology? :-)
If you can *hear* that rumble, then there is something *very* wrong
with your setup!
> The subwoofer is often a subliminal effect that is felt in the chest.
> Turn it off and you can really tell it's missing.
Yes indeed, but that has nothing to do with audibility.
--
Stewart Pinkerton | Music is Art - Audio is Engineering
Steven Sullivan
> Hi Rich,
> > I diagree. My speakers are flat to 20 hz without a
> sub, so I see no
> > reason to add one. All it will do is add distortion
> and change the
> > frequency response to be something other than flat.
> I am sure that there
> > are other people who have speakers flat to 20hz.
> That's what I used to think also. I have B&W801s,
> which aren't particularly bass-shy, and was convinced I
> didn't need a subwoofer.
Btw, what floorstanders are flat to 20 Hz?
> Now I have stereo subwoofers!
> It really can make a huge difference even with
> full-range speakers. Plus you can place the subwoofers
> and your main speakers where each produces the best
> sound for the frequency range they are reproducing,
> especially if multiple subs are used. It does require
> the proper crossover electronics with time delay
> capabilities for seamless integration.
Can someoen tell me, at what separation distance between
mains and subs, does time delay adjustment
really become (audibly) necessary?
--
-S.
"They've got God on their side. All we've got is science and reason."
-- Dawn Hulsey, Talent Director
Mkuller
>Btw, what floorstanders are flat to 20 Hz?
Uh, my Thiel 7.2s in my room. What type of speakers are you using?
Regards,
Mike
Tip
> Btw, what floorstanders are flat to 20 Hz?
When measured (derived from the impulse response) in my
room (i.e. with room gain), my B&W801s go below 20Hz
before steeply rolling-off. The 801s also came with a
line-level EQ device that supposedly extends the
anechoic response to 20Hz (I have it but didn't use it,
and I've also tried the EQ device Krell made for the
801s). The problem is that there is very little, if
any, information at that low of a frequency in music.
But I don't have subwoofers for subterranean bass
response, and in a sense, I really don't have "sub"
woofers at all, although they do go down to 14 Hz.
They really are just "woofers" (four 10" short-throw,
light diaphragm drivers per channel) and have a much
higher crossover point than any "normal" subwoofer
would. Their main advantage is that they can be
positioned in the room for the best, most
time-coherent, response (near the walls). The B&W801s
are positioned for best mid-range clarity (away from
the walls). I use digital time-domain EQ to correct
the response and digital crossovers with time delay to
integrate the woofers with the 801s.
> Can someoen tell me, at what separation distance
between
> mains and subs, does time delay adjustment
> really become (audibly) necessary?
It depends on the crossover frequency. Studies
(Blauert & Laws) have found the threshold of audibility
is approximately 3.2ms at 500 Hz, which would be a
distance of three to four feet. It would increase at
lower frequencies. I crossover at a relatively high
frequency and the acoustic center of my "woofers" is
four to five feet farther away from the listening
position than the woofer of the 801s. I apply a 3.8 ms
delay on my 801s which was determined from the measured
impulse response.
But you are correct when it comes to normal subwoofers
not needing time delay adjustment, unless the
subwoofers are placed near the listening position and
the main speakers are far away.
Regards,
Tip
Nousaine
>Tip <Tip_J...@comcast.net> wrote:
>> Hi Rich,
>
>> > I diagree. My speakers are flat to 20 hz without a
>> sub, so I see no
>> > reason to add one. All it will do is add distortion
>> and change the
>> > frequency response to be something other than flat.
>> I am sure that there
>> > are other people who have speakers flat to 20hz.
>
>> That's what I used to think also. I have B&W801s,
>> which aren't particularly bass-shy, and was convinced I
>> didn't need a subwoofer.
>
>Btw, what floorstanders are flat to 20 Hz?
None I've ever seen; including the Wilson's. Even when they have the speaker
displacement to accomplish 20 Hz 'stereo' locus will ensure modal peaks/dips at
higher frequencies making them less that optimally 'flat.'
>
>> Now I have stereo subwoofers!
>> It really can make a huge difference even with
>> full-range speakers. Plus you can place the subwoofers
>> and your main speakers where each produces the best
>> sound for the frequency range they are reproducing,
>> especially if multiple subs are used. It does require
>> the proper crossover electronics with time delay
>> capabilities for seamless integration.
>
Basically I truism.
>Can someoen tell me, at what separation distance between
>mains and subs, does time delay adjustment
>really become (audibly) necessary?
Well in my current application and my last listening room that distance would
be 7-meters, because you'd need to move the mouth of the speaker into the next
room. But even then delay wouldn't fix the problem. :-)
MYKEY
yes I am purposely boosting a very narrow band to make the speaker work
at 15 hz. with lots of headroom and voice coil to spare there is no damage
or distortion. I am limited by the size of the cabinet and the speaker
but not by the amp or signal chain. PS I push the loudness button.
I notice a great improvement especially with digital recordings. I think
this more closely duplicates the sound of a live performance since the
subsonic is lost from the limitations of any speaker alone.
The object is not to be loud, it is to sound good. The EQ is not a smiley
face.
from experimenting, I have decided that a preamp modified to 6hz-1Mhz
sounds much better than any expensive off the shelf preamp. I have
nicknamed this the "air sound". I do not except the limitations of modern
components; but strive for a sound that is "hi fi" to me. I invite you to try
fearlessly to move passed what is now considered hi fi. I think my hearing
range is much wider than 20-20khz and I want reproduction to match...
Nousaine
wrote:
>Only at very low SPLs, since the limit below 30-40Hz will be set by
>the Xmax of the speaker, which is *not* susceptible to EQ. IOW, a
>normal 15" driver not specifically designed for the ultra long throw
>needed for subwoofer use, simply can *not* move enough air to even be
>*audible* at 20Hz. I canna' change the laws o' physics, cap'n.....
Now stop that. My 15-inch subwoofer will produce 120 dB SPL @ 20 Hz @ 2-meters
with less than 10% distortion. Just because I need 8 15-inch drivers with 23mm
Xmax doesn't mean it can't be done :-0
Joseph Oberlander
Lol.
That's Nousaine for you :)
Or, you could just get 3-4 18 inchers.
Stewart Pinkerton
<josephob...@earthlink.net> wrote:
Surprisingly, that's likely to be less effective. I suspect that he's
using Adire Tempests or similar (TC Sounds?), and it's *very*
difficult to improve the 'bang for the buck' with any available 18"
driver. The 'vapourware' Stryke 15" seems to be the best in that
regard - if you can get hold of them!
That's the problem with ultra-low frequencies - there's very little
fancy resonance control or other difficult stuff required, it all
comes down to air displacement and power. It's perhaps the only area
left where the homebuilder really can exceed the capability of
anything commercially available. Try Googling on '12 Shivas dancing'
for an entry into the wonderful world of nearly infinite baffles! BTW,
my trusty slipstick suggests that I can achieve an easy 112-115dB SPL
in-room at 20Hz with just one pair of Tempests in the attic, firing
through a foot-square hole in the ceiling corner and driven by a
simple 250 watt 'plate' amplifier. Total cost around £800 plus some
simple woodworking, and very high WAF due to near-invisibility.
Now *that's* kickin' your ass! :-)
Tip
> Try Googling on '12 Shivas dancing'
> for an entry into the wonderful world of nearly
infinite baffles! BTW,
> my trusty slipstick suggests that I can achieve an
easy 112-115dB SPL
> in-room at 20Hz with just one pair of Tempests in the
attic, firing
> through a foot-square hole in the ceiling corner and
driven by a
> simple 250 watt 'plate' amplifier.
You mean something like this:
http://www.geocities.com/pnwright3/Gemini_subs.html
Is your attic ventilated to the outside? What do you
do about temperature extremes and moisture?
Regards,
Tip
Stewart Pinkerton
wrote:
>Hi Stewart,
>
>> Try Googling on '12 Shivas dancing' for an entry into the wonderful
>> world of nearly infinite baffles! BTW, my trusty slipstick suggests that
>> I can achieve an easy 112-115dB SPL in-room at 20Hz with just one
>> pair of Tempests in the attic, firing through a foot-square hole in the
>> ceiling corner and driven by a simple 250 watt 'plate' amplifier.
>
>You mean something like this:
>http://www.geocities.com/pnwright3/Gemini_subs.html
Yes indeed, if of slightly less displacement.... :-)
The nice thing about the Tempest is that if you short one of the voice
coils, it is naturally flat to an f3 of 20Hz in such an IB situation
and has an 8-ohm impedance. A 250watt/4 ohm 'plate' amp is more than
adequate to achieve Xmax at 20-30 Hz on a pair of these drivers, while
not at all stressing the voice coils. The coils are rated at 400 watts
each, so there are no significant high-level compression effects with
only 125 watts peak going through each one.
>Is your attic ventilated to the outside?
Yes, although the roof is insulated and the attic recives leakage
warmth from the 25x18 foot living room below it. It never gets down to
freezing point.
> What do you
>do about temperature extremes and moisture?
Although paper-based, the cone is epoxy-coated, and the attic room
does not experience extremes outside 5-30 Celsius and 40-80% RH (the
English midlands have a very temperate climate), so I don't anticipate
any problems from atmospheric variation.
Norman Schwartz
greatest improvements.
MYKEY
> As I see and can hear it, an inner ear transplant would be the mother of
> greatest improvements.
here is another system we modified for earthquake subsonic:
8X JBL 18" crown 5000
8X JBL 15" crown 5000
8X JBL 12" crown 5000
4X JBL Horn crown 3500
4X JBL tweet crown 3500
2X JBL 6 way digital Xover
The preamp was modified for frequency response 3hz-1mhz
the subs are crossed at 37hz. the tweets crossed at 7khz
does that require fcc approval?
Now we finally have some headroom, but the trouble was
when you turn it up loud the power to the building
collapses and the comes back. My friend moved this system
into his apartment. what a great way to make new friends with the neighbors
Bruce J. Richman
>As I see and can hear it, an inner ear transplant would be the mother of
>greatest improvements.
>
>
>
>
>
>
Only if it were made out of gold. :)
Bruce J. Richman
Nousaine
This is one of the reasons I use a basement. I'm thinking the biggest problemn
of a attic installation would be the heat-tunnel from the inside. I'm guessing
a large insulation blanket would help but I hate the thought of flying
fiberglass.
Nousaine
Not exactly. It's hard to find a long stroke 18-inch driver. Given the
available drive units at the time this woofer system was designed the most
commonly employed 18-inch woofer available only had 10-mm of clean stroke and
so about 60% of the Vd of one of my 15-inchers give that it had 50% more piston
area but only 45% of peak to peak stroke.
However I wasn't taking any chances; this infinite baffle has 8 removable
woofer panel and will accept 8 15 and 18-inch drivers or up to 16 12s.
Nousaine
wrote:
>
>On 26 Mar 2004 06:18:26 GMT, Joseph Oberlander
><josephob...@earthlink.net> wrote:
>
>>Nousaine wrote:
>>
>>> Stewart Pinkerton pat...@dircon.co.uk
>>> wrote:
>>>
>>>>Only at very low SPLs, since the limit below 30-40Hz will be set by
>>>>the Xmax of the speaker, which is *not* susceptible to EQ. IOW, a
>>>>normal 15" driver not specifically designed for the ultra long throw
>>>>needed for subwoofer use, simply can *not* move enough air to even be
>>>>*audible* at 20Hz. I canna' change the laws o' physics, cap'n.....
>>>
>>> Now stop that. My 15-inch subwoofer will produce 120 dB SPL @ 20 Hz @
>2-meters
>>> with less than 10% distortion. Just because I need 8 15-inch drivers with
>23mm
>>> Xmax doesn't mean it can't be done :-0
>>
>>Lol.
>>
>>That's Nousaine for you :)
>>
>>Or, you could just get 3-4 18 inchers.
>
>Surprisingly, that's likely to be less effective. I suspect that he's
>using Adire Tempests or similar (TC Sounds?), and it's *very*
>difficult to improve the 'bang for the buck' with any available 18"
>driver.
My drivers are custom 15-inch TC Sounds made from off-the-shelf parts. TC seems
to be the best current source for long travel suspension woofers. In my
particular case the drivers have a fairly high Fs (30 Hz) which turns into an
installed Fsb of 21 Hz when the air mass in the plenum gets added to the moving
mass. But, that still requires 18 dB of EQ at 12 Hz to make the system flat to
10 Hz and a Crown MAcro-Tech 5000VZ to drive the system to 120 Hz below 20 Hz.
Interestingly the system cannot be driven to full SPL at 10-16 Hz for fear of
popping a double vinyl window out of its frame.
Stewart Pinkerton
> I'm thinking the biggest problemn
>of a attic installation would be the heat-tunnel from the inside. I'm guessing
>a large insulation blanket would help but I hate the thought of flying
>fiberglass.
It's a sealed wooden plenum chamber, so you're only talking about
radiation losses through a couple of thick plastic-coated paper cones,
not convection. Since there's an open fireplace in the same room, it's
not a significant issue for me.
Michael Scarpitti
1. Diamond styli.
2. Westrex 45/45 system.
3. Vinyl (replaced shellac).
4. CD's.
Howard Ferstler
What kind of music or home-theater reproduction requires that kind of
subwoofer output power, Tom?
As a product reviewer, I have three systems at my place for reference
purposes as well as pleasure. One has a big Velodyne F1800RII for
main-channel work and a Hsu TN1220 for the center. (The Hsu is not
really needed, but I had the sub on hand and so I put it to work.) The
second has a "modified" SVS 16-46PC. The "modified" latter has the
enclosure inverted, with the driver facing up, Hsu style, and with the
grill replaced by another spaced-off wooden disc to reduce
grill-screen noise. In addition, the driver is upgraded to a
considerably heavier-duty, 12-inch TC systems job, and with the amp
power changed from 190 to 320 watts. (An upcoming article by me in The
Sensible Sound will discuss this mod, and a still later article will
involve a comparison between it and the Hsu TN1220 and also between it
and one of the SVS "Ultra" subs.) The third system has a Velodyne
FSR-12 servo that is small but decently potent in the area it
occupies.
The three systems occupy rooms of 3,400, 2,900, and 2,000 cubic feet,
and in each case the subs can generate all the low-bass realism
required with any acoustic music one might want to listen to, and the
two bigger ones can generate all the home-theater, adventure movie
bass the walls can stand. All are capable of going solid to 20 Hz,
with the modified SVS job strong right down to 17 Hz.
Is going beyond that point kind of gilding the lily when it comes to
practical subwoofer performance in typical home-listening rooms? I
mean, if one wants to generate "greater than reality" SPL levels
(sound-effects clashes, or whatever) or frequencies below what one
would hear at any live concert (certainly, any classical-music concert
that did not include a pipe organ) then maybe a wall-cracking
subwoofer is OK.
However, I find that kind of excess to be just that: excess when it
comes to practical home-music or home-theater listening requirements.
Supporting this kind of mega-subwoofer overkill probably misleads a
lot of audio enthusiasts who are mainly in it for the musical or
home-theater satisfaction, as opposed to owning what is essentially a
sound-effects-recording "rumbler" for the living room. Rather than
invest in a overkill subwoofer (as opposed to one that is just strong
and solid right down to 20 Hz or a tad below), perhaps the individual
should back off a bit and put their surplus cash into additional
recordings, a superior surround processor, or better satellite
speakers.
Subwoofers are fine, and I would not do without one for a minute.
However, one can go a bit over the top, I think.
Howard Ferstler
Nousaine
>nous...@aol.com (Nousaine) wrote
>> >>
>> >> Now stop that. My 15-inch subwoofer will produce 120 dB SPL @ 20 Hz @
>> 2-meters
>> >> with less than 10% distortion. Just because I need 8 15-inch drivers
>with
>> 23mm
>> >> Xmax doesn't mean it can't be done
>What kind of music or home-theater reproduction requires that kind of
>subwoofer output power, Tom?
Eric Bush confirmed several years ago that modern cd recordings can have
significant frequency content as low as 6 Hz. I own such a collection of cds.
My goal for subwoofers was partially based on Tom Holman's observation that 122
dB SPL at low frequencies may be a useful dynamic headroom limit. This system
will play any recorded program (which includes environmental sounds such as
radial engined aricraft, thunderstorms, trains and artillery) with no dynamic
limits.
ANY recording known at reference level. But, again, this is a reference system
used for professional evaluation. I've never claimed that everybody needs one.
>
>However, I find that kind of excess to be just that: excess when it
>comes to practical home-music or home-theater listening requirements.
>Supporting this kind of mega-subwoofer overkill probably misleads a
>lot of audio enthusiasts who are mainly in it for the musical or
>home-theater satisfaction, as opposed to owning what is essentially a
>sound-effects-recording "rumbler" for the living room.
You may also be excluding the crop of car-audio enthusiasts who are used to
getting 120 dB SPL in their cars. Shouldn't they be allowed to experience this
level of performance at home too?
Rather than
>invest in a overkill subwoofer (as opposed to one that is just strong
>and solid right down to 20 Hz or a tad below), perhaps the individual
>should back off a bit and put their surplus cash into additional
>recordings, a superior surround processor, or better satellite
>speakers.
Fully agreed.
>
>Subwoofers are fine, and I would not do without one for a minute.
>However, one can go a bit over the top, I think.
>
>Howard Ferstler
IMO there is no such thing as over-the-top for dynamic capability. If I have a
system that would produce 120 dB SPL+ (using 2 meters distance) over the
complete human sensory range in a very quiet room than you can play anything
from a soft breeze to a black powder cannon at reference level.
OTOH if you are a person who has no recordings that ever approach dynamics
limits of the media than you only need the dynamic capability required of the
source material. But, I know of only a handful of DIY systems that have
anything that comes near to reproducing the true low frequency dynamics of
known commercially avaliable cds.
S888Wheel
>Date: 4/14/2004 9:01 PM Pacific Standard Time
>Message-id: <c5l1e...@news1.newsguy.com>
>
>Eric Bush confirmed several years ago that modern cd recordings can have
>significant frequency content as low as 6 Hz. I own such a collection of cds.
>My goal for subwoofers was partially based on Tom Holman's observation that
>122
>dB SPL at low frequencies may be a useful dynamic headroom limit. This system
>will play any recorded program (which includes environmental sounds such as
>radial engined aricraft, thunderstorms, trains and artillery) with no dynamic
>limits.
>
>OTOH if you are a person who has no recordings that ever approach dynamics
>limits of the media than you only need the dynamic capability required of the
>source material. But, I know of only a handful of DIY systems that have
>anything that comes near to reproducing the true low frequency dynamics of
>known commercially avaliable cds.
The reproduction of a 6hz tone (I guess it could be called a tone) would be
utterly useless. It is completely inaudible. What are you trying to recreate at
that point? If some CDs have information at 6hz chances are there was something
wrong that put it there.
Nousaine
It may be "inaudible" as a pure tone but it's certainly a sensation of feel.
Even so would you consider an organ fundamental of a 32 Foot pipe (16 Hz)
inaudible? How about a 64-foot stop (8 Hz) inaudible? If they were than none of
these would have ever existed in musical history.
How about the pressure wave of a black powder cannon on Telarc's 1812 Overture?
Would the sub-20 Hz information be considered "inaudible?" Would you be
interested in auditioning that piece with a system that was capable of
reproducing the full spectrum of that recording such as you'd experience it if
you were at the performance?
If some CDs have information at 6hz chances are there was
>something
>wrong that put it there.
In rare case that's true. For example on Lyle Lovett's "Joshua Judges Ruth" cd
a low frequency accident occurs (seemingly a exit stairway door slam) in the
performance. But do you want to experience exactly what's been recorded or not?
As I've mentioned before environmental recordings such as thunderstorms have
significant low frequency content....would you have me exclude that experience?
Some modern car-audio bass recordings have tremendous low frequency content.
For example a Neurodisc tracks has a descending low frequency sweep that will
excite the 12 Hz structural resonance of my stick-frame house. Should I deny
myself that experience?
Some modern movie soundtracks have subway/locomotive clips with subsonic
content. I consider it my job to have a system that will playback these dvds
exactly as contained on the recording.
So, yes, accidents, foley effects, environmental sounds, bass-head cds and
anything else I can imagine; I want to be able to ne able to reproduce it as
captured on the recording.
As I mentioned earlier most enthusiasts don't need this capability but it is
attainable BUT ONLY with DIY systems.
andy
> IMO development has progressed so rapidly in the past 25 years that any
> reasonably interested enthusiast can now buy a system for 2-3 k that
> outperforms anything one could buy for any amount of money in 1975.
>
Do you think it is true for loudspeakers? I feel loudspeaker
technology moved much slower than electroniscs. People still enjoy
Klipsch, Kef 105, AR 10 PI. Not to mention the outstanding ESL (since
1957
There have been progresseses in science of material (kevlar,
beriliium) but nothing outstang from speaker design.
I may be wrong: opinions are welcome, then
> I love these threads though. They make me step back from my puny personal
> challenges at any given moment and appreciate just how well off I am today.
Stewart Pinkerton
From: nous...@aol.com (Nousaine)
>>Date: 4/14/2004 9:01 PM Pacific Standard Time
>>Message-id: <c5l1e...@news1.newsguy.com>
>
>>
>>Eric Bush confirmed several years ago that modern cd recordings can have
>>significant frequency content as low as 6 Hz. I own such a collection of cds.
>>My goal for subwoofers was partially based on Tom Holman's observation that
>>122
>>dB SPL at low frequencies may be a useful dynamic headroom limit. This system
>>will play any recorded program (which includes environmental sounds such as
>>radial engined aricraft, thunderstorms, trains and artillery) with no dynamic
>>limits.
>
>>
>>OTOH if you are a person who has no recordings that ever approach dynamics
>>limits of the media than you only need the dynamic capability required of the
>>source material. But, I know of only a handful of DIY systems that have
>>anything that comes near to reproducing the true low frequency dynamics of
>>known commercially avaliable cds.
>
>The reproduction of a 6hz tone (I guess it could be called a tone) would be
>utterly useless. It is completely inaudible.
It is however very *perceptible*.
> What are you trying to recreate at
>that point? If some CDs have information at 6hz chances are there was something
>wrong that put it there.
There is a good chance that such subsonic tones can exist on horror or
thriller movie soundtracks - they are very disturbing to humans.
S888Wheel
>Date: 4/15/2004 9:32 PM Pacific Standard Time
>Message-id: <c5nnl...@news3.newsguy.com>
One can feel a stiff breaze or being gabbed by the shoulders and shaken
vigourously (which can happen at hear 6hz with the right person shaking you)
>Even so would you consider an organ fundamental of a 32 Foot pipe (16 Hz)
>inaudible?
Boarderline. It is my undersytanding that one mostly feels this note.
How about a 64-foot stop (8 Hz) inaudible?
Yes. That would just be senseround effects.
If they were than none
>of
>these would have ever existed in musical history.
>
That's not rue.
>How about the pressure wave of a black powder cannon on Telarc's 1812
>Overture?
>Would the sub-20 Hz information be considered "inaudible?"
Yes I would. I would also consider it to be quite unpleasant. I would also bet
that by the time such a preasure wave is reproduced in playback it is both so
inacurate and so impossible for any listening room to contain that it is
nothing more than a cheesy effect.
Would you be
>interested in auditioning that piece with a system that was capable of
>reproducing the full spectrum of that recording such as you'd experience it
>if
>you were at the performance?
Aside from the fact that I have no desire to feel the shock wave of a real
cannon just because it was present at the live performance (along with any
number of nonaudible and undesirable perceptable phenomena) I am skeptical that
anything remotely accurate to that shock wave will be reproduced in playback.
Some people may get a buzz out of the subwoofers shaking the walls and being
felt down the block. I don't. That is all you can hope to get. By the way. Such
shock waves are not healthy. Is this not the origin of the term shell shocked?
>
> If some CDs have information at 6hz chances are there was
>>something
>>wrong that put it there.
>
>In rare case that's true. For example on Lyle Lovett's "Joshua Judges Ruth"
>cd
>a low frequency accident occurs (seemingly a exit stairway door slam) in the
>performance. But do you want to experience exactly what's been recorded or
>not?
>
Ecxactly? Probably not. It may have been 99 degrees and near 100% humidity and
the soundboard operator may have been stinking of garlic and onions. And I
don't want to feel the shock waves of real cannons.
>As I've mentioned before environmental recordings such as thunderstorms have
>significant low frequency content....would you have me exclude that
>experience?
I never said one should exclude significant low frequency content. I said
anything at 6hz is useless. I guess if you want to shake the walls and be
pounded by shock waves they are in fact usefull. No, I don't wish to deprive
you of what you enjoy.
>
>Some modern car-audio bass recordings have tremendous low frequency content.
Yes I know. I often hear cars well before I see them on the road. I would not
want to be in them however. I don't even like being near them.
>For example a Neurodisc tracks has a descending low frequency sweep that will
>excite the 12 Hz structural resonance of my stick-frame house. Should I deny
>myself that experience?
LOL no. I should.
>
>Some modern movie soundtracks have subway/locomotive clips with subsonic
>content. I consider it my job to have a system that will playback these dvds
>exactly as contained on the recording.
I suppose so. One movie was shot in smellorama as well. I find both quite
anoying.
>
>So, yes, accidents, foley effects, environmental sounds, bass-head cds and
>anything else I can imagine; I want to be able to ne able to reproduce it as
>captured on the recording.
I wouldn't want to deny you your pleasures. I will say that 6hz tones in
playback are useless for me. And undesirable.
>
>As I mentioned earlier most enthusiasts don't need this capability but it is
>attainable BUT ONLY with DIY systems.
>
>
>
>
>
>
I'm just not interested in shaking the walls, or having the sensation of my
insides being assulted.
Cossie
news:RDVfc.156341$JO3.94808@attbi_s04...
>
> Yes I would. I would also consider it to be quite unpleasant. I would also
bet
> that by the time such a preasure wave is reproduced in playback it is both
so
> inacurate and so impossible for any listening room to contain that it is
> nothing more than a cheesy effect.
>
I generally agree with this statement as it pertains to home audio.
However, I happen to know a couple of engineers at a pro speaker
manufacturer who could demonstrate some REAL bass for you. And I don't mean
highly distorted, "thump". These are people who specialize in making low
distortion, hi output subs. One of these gentlemen holds 18 patents in the
field of speaker design and used to levitate objects for Nasa research using
sound waves generated by his drivers. His company has since produced
drivers that have been used by researchers to study subsonic communication
between pachiderms. Those same drivers are available for sound
reinforcement, and as a matter of fact, George Lucas just installed some in
his home theater. Low distortion subsonics CAN be done, but they are
probably nothing like what you have experienced, and the drivers reguired
are not typical magnets and cones. Anyone who says they can produce
subsonics with a home made box is probably fooling themselves. Or if they
DO have system that will go that low, I can almost guarantee that the
distortion is very high.
Bill Balmer
Bromo
<billb...@worldnet.att.net> wrote:
Never minding the probability that the sound engineers making source
materials for movies, tend to (in many cases) make the bass a high sound
that then slews downward rather than be a sharp thud or crack.
Joseph Oberlander
> Aside from the fact that I have no desire to feel the shock wave of a real
> cannon just because it was present at the live performance (along with any
> number of nonaudible and undesirable perceptable phenomena) I am skeptical that
> anything remotely accurate to that shock wave will be reproduced in playback.
> Some people may get a buzz out of the subwoofers shaking the walls and being
> felt down the block. I don't. That is all you can hope to get. By the way. Such
> shock waves are not healthy. Is this not the origin of the term shell shocked?
They use small cannons at a fair ways off and safe distance.
The low frequency information isn't that large, actually - most of
it is firmly in the directional range other than the shockwave effect
which is definately *not* possible to reproduce in a recording.
The problem isn't the medium(24/96 could do it), but that we have
no microphone that can handle such a quick and powerful impulse
and record it properly. It would also mess up speakers as well,
obviously.
MIKE
limit of a string bass - about 38 hz unless a fifth string is used to go
down to 32 hz. Spending a fortune to let you rattle the windows and
loosen construction nails is foolish. One good sub is enough for an
average size room.
-MIKE
Stewart Pinkerton
<billb...@worldnet.att.net> wrote:
>Low distortion subsonics CAN be done, but they are
>probably nothing like what you have experienced, and the drivers reguired
>are not typical magnets and cones. Anyone who says they can produce
>subsonics with a home made box is probably fooling themselves. Or if they
>DO have system that will go that low, I can almost guarantee that the
>distortion is very high.
Not necessarily. It's all about displacement, and an array of
long-throw but otherwise conventional 15" drivers, which can have a
displacement of 5 litres *each*, can certainly produce 110dB at 6Hz in
a normal domestic listening room, using the popular 'infinite baffle'
arrangement with roof space or basement loading. You might find the
experience quite nauseating, but it can certainly be done with
conventional subwoofer drivers such as the Adire Tumult working at low
distortion within their Xmax limits.
Al
news:c5p02...@news3.newsguy.com...
> >
> > IMO development has progressed so rapidly in the past 25 years that any
> > reasonably interested enthusiast can now buy a system for 2-3 k that
> > outperforms anything one could buy for any amount of money in 1975.
> >
> Do you think it is true for loudspeakers? I feel loudspeaker
> technology moved much slower than electroniscs. People still enjoy
> Klipsch, Kef 105, AR 10 PI. Not to mention the outstanding ESL (since
> 1957
> There have been progresseses in science of material (kevlar,
> beriliium) but nothing outstang from speaker design.
> I may be wrong: opinions are welcome, then
I'm having very hard time replacing the never-forgotten Kef 104aB ...in my
heart at least.
Joseph Oberlander
OTOH, organ pedals go down to about 18-20hz.
Penury
<billb...@worldnet.att.net> wrote:
>However, I happen to know a couple of engineers at a pro speaker
>manufacturer who could demonstrate some REAL bass for you. And I don't mean
>highly distorted, "thump". These are people who specialize in making low
>distortion, hi output subs. One of these gentlemen holds 18 patents in the
>field of speaker design and used to levitate objects for Nasa research using
>sound waves generated by his drivers. His company has since produced
>drivers that have been used by researchers to study subsonic communication
>between pachiderms. Those same drivers are available for sound
>reinforcement, and as a matter of fact, George Lucas just installed some in
>his home theater. Low distortion subsonics CAN be done, but they are
>probably nothing like what you have experienced, and the drivers reguired
>are not typical magnets and cones. Anyone who says they can produce
>subsonics with a home made box is probably fooling themselves. Or if they
>DO have system that will go that low, I can almost guarantee that the
>distortion is very high.
Sounds like your refering to Tom Danley and his SevoDrive Subs.
The DIYers who are building subs that deliver subsonics are not
usually building "boxes". They are using multi woofers in an IB
arrangement. To see some examples, check:
http://home.comcast.net/~ttriff//page4IB-Gallery3.html
-=Bill Eckle=-
ab...@wmeckle.com
Vanity Web pages at:
http://www.wmeckle.com
Walter Bushell
s888...@aol.com (S888Wheel) wrote:
<snip>
> I never said one should exclude significant low frequency content. I said
> anything at 6hz is useless. I guess if you want to shake the walls and be
> pounded by shock waves they are in fact usefull. No, I don't wish to deprive
> you of what you enjoy.
And be sure to get a sign off from a competent structural engineer,
before installing.
Nousaine
Telarc's 1812 and Wellington's Victory have content below 10 Hz. Neurodic's
"Pure and Perfect Bass" has a descending frerquency sweep that will excite the
12 Hz structural resonance in a stick-frame home.
Walter Bushell
Joseph Oberlander <josephob...@earthlink.net> wrote:
<Snip>
>
> They use small cannons at a fair ways off and safe distance.
>
> The low frequency information isn't that large, actually - most of
> it is firmly in the directional range other than the shockwave effect
> which is definately *not* possible to reproduce in a recording.
>
> The problem isn't the medium(24/96 could do it), but that we have
> no microphone that can handle such a quick and powerful impulse
> and record it properly. It would also mess up speakers as well,
> obviously.
Ok, you could put it in in post production digitally. "Warning
attempting to play back this recording at realistic levels will damage
your speakers and ears. You have been warned."
Cossie
news:wAqgc.18023$0b4.24370@attbi_s51...
>
> Sounds like your refering to Tom Danley and his SevoDrive Subs.
> The DIYers who are building subs that deliver subsonics are not
> usually building "boxes". They are using multi woofers in an IB
> arrangement. To see some examples, check:
> http://home.comcast.net/~ttriff//page4IB-Gallery3.html
>
Interesting stuff. I'm curious about how these systems would perform;
particularly as relates to the room resonance, distortion, and construction
techniques. I have never seen an infinite baffle system like this. I do
know that the folks at Servodrive (yes, it was Tom to whom I was referring,
along with John Halliburton, whom I know better than I know Tom) produce
some subs that produce significantly lower distortion than the rooms in
which they're used.
Bill Balmer
Stewart Pinkerton
Maybe, but the midrange was shite - flat and lifeless, as with all
those 'classic' bextrene-coned KEFs.
Walter Bushell
Did any one mention Double Blind Testing?
Nousaine
I can't speak of the systems on that site but I have measured 5 large
displacement high powered systems. For example my systems (8 15-inch drivers
Infinite Baffle into basement) will produce 124 dB from 10 to 62 Hz with 10% or
less distortion at 2 meters in-room.
Room modes do not change at all because those are a function of room
dimensions. If the walls are concrete the modal peaks will be relatively
magnified compared to drywall which offers more low frequency absorption.
Soundproofing with drywall on resilient channels is also a good thing because
it supplies low frequency absorption.
IMO the biggest problem at low frequencies in rooms is many of them do not have
enough low frequency absorption to tame modal peaks. OTOH the price for this
absorption is more speaker displacement to maintain pressure.
The single biggest in-room problem is snubbing clatters, rattles and buzzes
from objects placed on walls or even in cabinets. My glass and silverware will
chime in the kitchen when testing good subwoofers but in the listening room
this is not audible.
MYKEY
> On Sun, 18 Apr 2004 07:43:20 GMT, "Al" <afrie...@nyc.rr.com> wrote:
>
> >"andy" <andyl...@excite.com> wrote in message
> >news:c5p02...@news3.newsguy.com...
> >> >
> >> > IMO development has progressed so rapidly in the past 25 years that any
> >> > reasonably interested enthusiast can now buy a system for 2-3 k that
> >> > outperforms anything one could buy for any amount of money in 1975.
> >> >
> >> Do you think it is true for loudspeakers? I feel loudspeaker
> >> technology moved much slower than electroniscs. People still enjoy
> >> Klipsch, Kef 105, AR 10 PI. Not to mention the outstanding ESL (since
> >> 1957
> >> There have been progresseses in science of material (kevlar,
> >> beriliium) but nothing outstang from speaker design.
> >> I may be wrong: opinions are welcome, then
the magnets have come a long way, when you combine the rare earth
magnet on a cast frame with a kevlar cone and a voice coil with Kapton
insulation, your really looking at a step up (look at EVX speakers)
Also we have seen woofer sizes larger than 18" offered including
22" and 30". That gives hope to your subsonic.
Take your KEF speakers and rewire them for triamp with one subwoofer,
they can live a new life.
This system sitting here was built for less than $1000 and puts many high
end systems to shame. Eviction no problem: Sentry 3 cabinets with JBL
15" woofers purchased at garage sale for $50. Midrange I used JBL
control 1 bookshelf speakers $150, tweeters three per side optimus
dipole tweeter on sale $7 each. Harmon Kardon stack with 5 channel amp,
subs in mono $500. Rane three way electronic crossover $225.
This system does everything a fancy system does, plus I can change
and rearrange the sound, crossover points of the speakers anytime I want.
Nousaine
>Jumping in
>
>Did any one mention Double Blind Testing?
No; you wanna' go first? :-)
Stephen McLuckie
news:c60s1...@news4.newsguy.com...
> Jumping in
>
> Did any one mention Double Blind Testing?
No, what on earth is that?
Stephen
Howard Ferstler
because I could not find the thread on the Google groups
pages, even though I did my initial commentary from that
source. So goes the strangeness of computerland.
Nousaine wrote:
>
> fers...@yahoo.com (Howard Ferstler) wrote:
>
> >nous...@aol.com (Nousaine) wrote
>
> >> >>
> >> >> Now stop that. My 15-inch subwoofer will produce 120 dB SPL @ 20 Hz @
> >> 2-meters
> >> >> with less than 10% distortion. Just because I need 8 15-inch drivers
> >with
> >> 23mm
> >> >> Xmax doesn't mean it can't be done
> >What kind of music or home-theater reproduction requires that kind of
> >subwoofer output power, Tom?
> Eric Bush confirmed several years ago that modern cd recordings can have
> significant frequency content as low as 6 Hz. I own such a collection of cds.
I have a couple like that, myself. However, I would say that
few of those discs that exhibit super-low content have much
to offer in the way of meaningful music aesthetics. It may
be fun to experience the low, low rumble or booms of such
discs maybe one or two or three times (the second and third
times being show-off sessions for a guest), but listening to
such material over and over for musical enjoyment is
certainly not something I would care to do - and I doubt
that most music enthusiasts would care to do so, either.
The fact is that most digital recordings (particularly the
dull baroque and classical stuff I listen to for pleasure)
do not have all that much super-low bass, and in many cases
the super-low bass certain discs have are hall-noise
artifacts that are more annoying than musically significant.
Many recording engineers would like to get rid of such
anomalies rather than have them reproduced.
> My goal for subwoofers was partially based on Tom Holman's observation that 122
> dB SPL at low frequencies may be a useful dynamic headroom limit.
For what? I certainly do not know of any live, acoustic
music situation that would require something like that.
Well, I take that back. I attended a Stan Kenton concert
years ago and even at the back of the hall the high-octane
sound from the trumpets was unsettling. However, no
subwoofer would be required to handle that kind of material.
I have doubts that any midrange and tweeter combination in a
home-audio system could deal with it, either.
> This system
> will play any recorded program (which includes environmental sounds such as
> radial engined aricraft, thunderstorms, trains and artillery) with no dynamic
> limits.
Fun for some, but not for me. I guess I am getting old.
Actually, I feel similarly about the systems I mentioned
above. My subs can easily get under the low-end sounds of
the vast bulk of the musical and home-theater material I
have encountered as a reviewer and enthusiast. In my three
rooms, all can easily deliver realistically high levels down
to 20 Hz, and none roll off appreciably down to that
frequency. At the high levels that I occasionally use when
testing subs, I find that my rooms generate so many noise
artifacts of their own (wall-hung pictures, windows, doors,
and shelf-located knick-knacks rattling aplenty) that
worrying about the sound of the sub itself becomes
secondary.
On the other hand, at levels that simulate a live-music
event (note that this does not include rock-concert live
sound, since I never attend such get togethers anyway) the
room noises disappear and my own subs just loaf along. No
need for them to be able to play louder or lower - even for
product- and music-reviewing purposes.
Sure, there may be an occasional boomer recording (CD or
DVD) that should tax a typical super sub (as opposed to a
home-built super-duper sub played at levels one would never
encounter at either a live, acoustic-instrument concert or
in a killer-grade movie theater), but I do not think that
kind of recording is something most people would miss if
they never heard it. And while you note that your system is
used for professional evaluation, you also note that not
everybody needs one for that kind of performance. The reason
most do not need it is that most do not listen to material
of a kind that would require a sub of that kind to be
installed in their homes. Hence, having a system that can
deal with that kind of material at those frequencies and at
those levels is not based upon a need to "reference"
material that anyone would normally purchase. All one needs
for reference work is a system that would equal, or maybe
slightly surpass, what a serious, realism-oriented music or
home-theater enthusiast would want.
> >However, I find that kind of excess to be just that: excess when it
> >comes to practical home-music or home-theater listening requirements.
> >Supporting this kind of mega-subwoofer overkill probably misleads a
> >lot of audio enthusiasts who are mainly in it for the musical or
> >home-theater satisfaction, as opposed to owning what is essentially a
> >sound-effects-recording "rumbler" for the living room.
> You may also be excluding the crop of car-audio enthusiasts who are used to
> getting 120 dB SPL in their cars. Shouldn't they be allowed to experience this
> level of performance at home too?
Well, adult people should be allowed to do what they want,
including wrecking their hearing. (OK, loud bass will not
normally do that, but if we are talking about flat output
then we are going to have to admit that frequencies above
the bass range will be equally loud, and those can harm
one's hearing.) Actually, I find car "hi-fi" to be an
oxymoron, because there is just no way to get "realistic"
musical sound from a motor vehicle that is generating road
and motor noise. Again, I say this as a baroque and
classical freak who likes quiet backgrounds underneath his
music.
OK, I am a fuddy duddy, but I must say that it mystifies me
that anyone would want 120-dB sounds in their cars or in
their home systems. However, I suppose that if someone wants
to have 120-dB bass at 15 Hz in their car or living room
they should go ahead and have it. Not my bag, but to be
truthful a lot of things that people do are not my bag.
> Rather than
> >invest in a overkill subwoofer (as opposed to one that is just strong
> >and solid right down to 20 Hz or a tad below), perhaps the individual
> >should back off a bit and put their surplus cash into additional
> >recordings, a superior surround processor, or better satellite
> >speakers.
> Fully agreed.
And I have to agree with you when it comes to individuals
who want to really pull out all the subwoofer stops.
However, I do not think that super-duper subwoofer
performance is particularly important when it comes to most
musical or home-theater situations. Actually, it almost
looks like an automotive horsepower race, rather than
something that relates to the accurate reproduction of
live-music-style sound.
> >Subwoofers are fine, and I would not do without one for a minute.
> >However, one can go a bit over the top, I think.
> IMO there is no such thing as over-the-top for dynamic capability. If I have a
> system that would produce 120 dB SPL+ (using 2 meters distance) over the
> complete human sensory range in a very quiet room than you can play anything
> from a soft breeze to a black powder cannon at reference level.
No doubt. However, the vast bulk of all recordings are not
in this category. I suppose for me the question involves
whether we are talking about an audio system as a musical
(or home-theater) reproducer or whether we are talking about
a device that is basically a sound-effects machine that
makes use of exotic recordings as source material.
> OTOH if you are a person who has no recordings that ever approach dynamics
> limits of the media than you only need the dynamic capability required of the
> source material. But, I know of only a handful of DIY systems that have
> anything that comes near to reproducing the true low frequency dynamics of
> known commercially avaliable cds.
Again, there are commercially available CDs that are maybe
as you say, but I would guess that they are musical dead
ends - at least by my rarefied standards.
I mean, I have a copy of one or two Bass Mekanic discs that
certainly go low enough. (I got these to help me evaluate
subs and not to listen to for fun. Indeed, I would go out of
my mind if I had to listen to them for musical pleasure.)
Ironically, I had a buddy from out of town drop in some time
back and I put one of the discs on for him and he flipped
out. He went out and bought a copy (and probably purchased
other Mekanik discs, too, for all I know), and now he
listens to them for pleasure! He has a pair of Velodyne
HGS-15 subs, and I suppose they do the trick pretty good,
even if they will not go all the way to the bottom.
Takes all kinds.
Howard Ferstler