Wireless pranksters tune in to burger king
David Platt
I bet that made 'em drop their donuts.
John Higdon
wrote:
> http://news.bbc.co.uk/2/hi/americas/3385743.stm
>
> I bet that made 'em drop their donuts.
My friends and I used to do this sort of thing from time to time when we
were kids. It never became a national news story, however.
Hell, back before KDFC (AM) got its PSSA, we would sometimes do
maintenance beginning at midnight. We would usually give an ID and then
welcome the nearby drive-in theater patrons to our listening audience.
Of course, that was the end of the picture show whether they planned it
that way or not.
--
John Higdon | Email Address Valid | SF: +1 415 428-COWS
+1 408 264 4115 | Anytown, USA | FAX: +1 408 264 4407
Jeff Liebermann
wrote:
>http://news.bbc.co.uk/2/hi/americas/3385743.stm
>I bet that made 'em drop their donuts.
Yawn. Old news. Been doing that for years.
http://www.bearcat1.com/fastfood.htm
http://www.witchdr.net/scanner/frequencies/fastfood.htm
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# je...@comix.santa-cruz.ca.us
# 831.421.6491 digital_pager je...@cruzio.com AE6KS
David Platt
Jeff Liebermann wrote:
> Yawn. Old news. Been doing that for years.
> http://www.bearcat1.com/fastfood.htm
> http://www.witchdr.net/scanner/frequencies/fastfood.htm
Damn, how unfashionable of me not to know that.
David Platt
John Higdon wrote:
> My friends and I used to do this sort of thing from time to time when we
> were kids. It never became a national news story, however.
Sounds like everybody's been doing it except me.
Philip J. Koenig
That story put a big smile on my face yesterday. :-)
--
* Few people are capable of expressing with equanimity opinions which *
* differ from the prejudices of their social environment. Most people are *
* even incapable of forming such opinions. -- Albert Einstein *
* *
* To send email, remove numbers and spaces: pjkusenet64 @ ekahuna27 . com *
* Simple answers are for simple minds. Try a new way of looking at things. *
Philip J. Koenig
cruz.ca.us (Jeff Liebermann) writes...
> On Sat, 10 Jan 2004 18:43:18 -0800, David Platt <pl...@mail.com>
> wrote:
>
> >http://news.bbc.co.uk/2/hi/americas/3385743.stm
> >I bet that made 'em drop their donuts.
>
> Yawn. Old news. Been doing that for years.
> http://www.bearcat1.com/fastfood.htm
> http://www.witchdr.net/scanner/frequencies/fastfood.htm
Now those are some coooool resources!
It's all got a new twist now that businesses are flocking to cheap,
commodity, unsecured WiFi-based equipment like cash registers. I
will tip my hat to the first person that gives themselves a nice
"hacker discount" at one of those WiFi-based cash registers.
(I seem to recall reading a story a few months back where Best Buy
had to get rid of or at least lock-down those after someone disrupted
some of them.)
DCT Dictator
>
>It's all got a new twist now that businesses are flocking to cheap,
>commodity, unsecured WiFi-based equipment like cash registers. I
>will tip my hat to the first person that gives themselves a nice
>"hacker discount" at one of those WiFi-based cash registers.
A Cannery Row restaurant uses a paperless/wireless ordering system.
Prankster could have a field day. How would it look to see a deuce
table get seven lobsters?
--
moblog at http://dctdctator.textamerica.com/
Richard Steinfeld
Is this anything like "LSMFT" or "CIE2WONOKCWMKOOMRDLFC?"
Richard?
"John Higdon" <absolutel...@verislimesucks.com> wrote
in message
news:absolutely-no-spam-0...@equine.announcetech.com...
John Higdon
"Richard Steinfeld" <rgsteinBUT...@sonic.net> wrote:
> PSSA?
> Is this anything like "LSMFT" or "CIE2WONOKCWMKOOMRDLFC?"
Post Sunset Authority. It is a standard industry abbreviation.
Richard Steinfeld
> In article <j%lMb.8040$XF6.1...@typhoon.sonic.net>,
> "Richard Steinfeld" <rgsteinBUT...@sonic.net>
wrote:
>
> > PSSA?
> > Is this anything like "LSMFT" or
"CIE2WONOKCWMKOOMRDLFC?"
>
> Post Sunset Authority. It is a standard industry
abbreviation.
Yes, John, and....?
What industry? What does it mean? Come on, John: I'm
beginning to feel like I'm trying to get basic information
out of the Bush administration.
I was a combo operator at a classical FM station. I never
heard this term. We didn't have AM, which ain't so good for
classical music. Tolerable with various forms of automatic
level controls, compression/expansion, etc.
Something to do with various changes that some AM stations
must do relative to their license after sunset?
Daylight-only license? Reduce power after dark?
So, spiel!
Richard
John Higdon
"Richard Steinfeld" <rgsteinBUT...@sonic.net> wrote:
> I was a combo operator at a classical FM station. I never
> heard this term. We didn't have AM, which ain't so good for
> classical music. Tolerable with various forms of automatic
> level controls, compression/expansion, etc.
I see. You were so specialized with a bottom-feeding job at an FM that
you didn't feel the need to take a little initiative to learn something
about the industry that you were moonlighting in? BTW, KDFC (the AM
station I was talking about in my little story) was a classical station
for about forty years. Someone should have told Ed Davis that AM "ain't
so good for classical music".
> Something to do with various changes that some AM stations
> must do relative to their license after sunset?
> Daylight-only license? Reduce power after dark?
After PSSA formulae were adopted by the commission, daytimers could
either continue to go off the air at sunset or transmit with a
(sometimes) greatly reduced power.
> So, spiel!
Here's a bonus: PSA, or Pre-Sunrise Authority. In those months when
local sunrise occurs after 6AM, daytimers can sign on at 6AM with
reduced power. This is separate from PSSA, and specifies a different
power level.
You actually worked in broadcasting and no one ever discussed this in
your presence. Amazing.
Richard Steinfeld
> In article <0UKQb.10682$XF6.2...@typhoon.sonic.net>,
> "Richard Steinfeld" <rgsteinBUT...@sonic.net>
wrote:
>
> > I was a combo operator at a classical FM station. I
never
> > heard this term. We didn't have AM, which ain't so good
for
> > classical music. Tolerable with various forms of
automatic
> > level controls, compression/expansion, etc.
>
> I see. You were so specialized with a bottom-feeding job
at an FM that
> you didn't feel the need to take a little initiative to
learn something
> about the industry that you were moonlighting in?
Bottom-feeding? Moonlighting? Whatever did I say that made
you come to such conclusions?
Now, now, John, don't be so prejudiced! I have extensive
experience in many areas of music and audio. From my
questions, you should have been able to clearly discern that
I'm dead-on about the concepts, just not the actual
acronyms. I was hired at WCRX because I was a good
announcer, knew a lot about the technology, could handle
emergencies on the air, and unlike many people who have
worked in classical music broadcasting, I actually know a
lot about the music. I have never worked in AM, nor am I
deeply involved with it because it is not a hi-fi medium and
I'm not into the content.
BTW, KDFC (the AM
> station I was talking about in my little story) was a
classical station
> for about forty years. Someone should have told Ed Davis
that AM "ain't
> so good for classical music".
>
John, perhaps you should think about the special
requirements of classical music audio and how they relate to
AM transmission. Commercial popular music, which dominates
the AM spectrum, has a limited dynamic range and usually a
limited frequency range. That's just the nature of it. The
high-frequency limit is governed by the actual carrier wave
frequency. Thus, a station at the bottom of the AM dial has
a limit that would intrude on the requirements, let's say,
of jazz. A station toward the upper end of the AM dial can
actually do a fairly good job of handling the frequency
ranges of all types of music.
Popular music works well with AM. As you should be aware,
the AM technology is very susceptable to noise and
interference. These factors cause a severe limit to the
practical dynamic range -- the difference between loud and
quiet music -- that the medium can successfully transmit.
The further from the transmitter that the listener is, the
worse these problems become. For example, given the location
of the former KDFC tower, around Foster City, if I recall,
the quality of reception in San Francisco and the East Bay
was marginal at best. The very limited signal-to-noise ratio
("headroom" if you like) of AM really digs into the music.
A symphony can have a dynamic range that taxes the abilities
of fine audiophile equipment to reproduce accurately. A
piece of music can go from an unaccompanied solo flute to
the entire orchestra playing flat out. For example, I was
just listening to the Berg violin concerto which goes from a
quiet solo violin to short sections of almost deafening
tuttis. The original mono FM parameters were so advanced
before 1940 that the technology can can easily handle music
of this type; mono FM is just about on a par with the
compact disk. The audio dynamic range "eaten" by the stereo
pilot signal (the "subcarrier") reduces this dynamic range
by around 20 percent. This reduction of range is clearly
visible on a radio station's modulation meter when switching
the transmitter betwen mono and stereo modes. The dynamic
range in stereo still affords at least 60db, which is
adequate for a fair amount of classical music. For various
reasons that I won't get into here, automatic signal
processing is applied to almost all FM music signals. When
more of the dynamic range is eaten by additional subcarrier
signals, that dynamic range is reduced further, requiring
heavier processing. When I worked in the medium, non-public
content was piggybacked onto FM -- content such as elevator
music and stock tickers.
Interestingly, my station, WCRX, transmitted on the same
channel as KDFC-FM, had a non-public subcarrier, and made
exactly the same horrible noises as did KDFC befire
Bonneville Broadcasting bought the station. You could really
hear that junk in the audio when the music got quiet. In
fact, I couldn't stand the noise and distortion of KDFC. The
combination of classical content with more than one
subcarrier is deadly to the audio. So, what I'm saying is
that with FM stereo, there can be severe problems that
interfere with the listening quality of classical music
reception. With AM, the problems are a lot worse given the
noise problem. In order for classical music to be listenable
over AM, the quiet passages have to be made louder and the
loud passages have to be made quieter: "homogenized" if you
prefer. Ironically, the flattening out of the dynamics in AM
classical music transmission actually improves the practical
listening experience in a noisy location, such as a car. But
overall, AM is a terrible transmission medium for classical
music.
>Someone should have told Ed Davis that AM "ain't
> so good for classical music".
From the quality of the signals that Mr. Davis put into the
air, he appeared to be deaf. I recall the awful "squiggling"
noises with which his FM signal was always plagued as the
station sounded in both San Francisco and the East Bay.
Let's face it: the man transmitted crappy audio. KKHI,
although lower-powered and high-falutin, put out a cleaner
signal. With audio quality like this pumped into the air,
for a person who loves classical music, there's no incentive
to invest in an audiophile FM tuner.
>" You actually worked in broadcasting and no one ever
discussed this in
> your presence. Amazing."
>
"...you didn't feel the need to take a little initiative to
learn something
> about the industry that you were moonlighting in? "
You know, John, it might behoove you to have read what I
wrote before putting your condescending words into the
ether. You may have gleaned from what I initially wrote that
I do indeed know something about the traditions of day vs.
night power and licensing in AM broadcasting. I grew up in a
place that had simulcasted classical music over AM and FM
over two outlets: WNYC and WQXR. In addition, we had FM-only
classical broadcasters at various times: WNCN and WBAI come
to mind. We also had daylight-only licenses and
sunset-reduced-power operators on AM. I have a rich history
of listening to and analyzing the properties of broadcast
signals. What I wrote in this post should illustrate the
initiative with which I've learned something about the
industry.
Please remember this before you put down anyone else who
just may be an expert, someone who just might know a hell of
a lot more than you do about the subject at hand.
Richard
Jeff Liebermann
<rgsteinBUT...@sonic.net> wrote:
>Ironically, the flattening out of the dynamics in AM
>classical music transmission actually improves the practical
>listening experience in a noisy location, such as a car. But
>overall, AM is a terrible transmission medium for classical
>music.
What's your opinion of classical music over DRM (Digital Radio
Mondaile) on AM and SW frequencies? In "robust mode 3", it will do
20dB S/N ratio up to 10Khz with a strong signal and low bit error
rate. There are about 50 broadcasters, all outside the US.
There are several test files near the bottom of:
http://drm.sourceforge.net
Links:
http://www.drm.org
http://www.drmrx.org/
There's also iBiquity, which I haven't had time to tinker with. Since
there are only 4 stations using it in the US (KROQ, WJLD, WOR, WRAL),
methinks I can wait.
I have my opinions, but I wanna hear yours.
--
Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
(831)421-6491 pgr (831)336-2558 home
http://www.LearnByDestroying.com AE6KS
je...@comix.santa-cruz.ca.us je...@cruzio.com
John Higdon
"Richard Steinfeld" <rgsteinBUT...@sonic.net> wrote:
> Bottom-feeding? Moonlighting? Whatever did I say that made
> you come to such conclusions?
The way you snidely asked the question, as if I had made up the
appreviation to sound "in" or "cool" when it fact it was a standard
term, much like "FCC".
> John, perhaps you should think about the special
> requirements of classical music audio and how they relate to
> AM transmission.
[Whole big diatribe about the inferiority of AM transmission, deleted.]
Oh, please. Been there, done that, have a closet full of T-shirts. Not
all classical listening is done with crackpot audio gear. Some of it is
done as background to other activities, and AM radio works just fine for
that. And when one drives in a car, the limited dynamic range of AM is a
feature, not a bug.
> Interestingly, my station, WCRX, transmitted on the same
> channel as KDFC-FM, had a non-public subcarrier, and made
> exactly the same horrible noises as did KDFC befire
> Bonneville Broadcasting bought the station.
Baloney. When I took on KDFC as chief engineer in the eighties, there
was no way, with any modern radio, that you could tell that the station
had TWO subcarriers. It didn't make any "horrible noises", particularly
after I installed then-current state of the art exciters and subcarrier
gear.
> From the quality of the signals that Mr. Davis put into the
> air, he appeared to be deaf. I recall the awful "squiggling"
> noises with which his FM signal was always plagued as the
> station sounded in both San Francisco and the East Bay.
I don't know when you listened to the station, but it certainly wasn't
when I was engineeering it...and it was my ear, not Davis' that
determined the quality at that time.
> Let's face it: the man transmitted crappy audio. KKHI,
> although lower-powered and high-falutin, put out a cleaner
> signal. With audio quality like this pumped into the air,
> for a person who loves classical music, there's no incentive
> to invest in an audiophile FM tuner.
If you think KKHI was the be-all and end-all of audio quality, we don't
have much to talk about.
> You know, John, it might behoove you to have read what I
> wrote before putting your condescending words into the
> ether. You may have gleaned from what I initially wrote that
> I do indeed know something about the traditions of day vs.
> night power and licensing in AM broadcasting.
Then why did you ask such a silly question in such a condescending
manner?
> Please remember this before you put down anyone else who
> just may be an expert, someone who just might know a hell of
> a lot more than you do about the subject at hand.
Actually, from your long diatribe, it would appear that I was pretty
much on the mark. What makes you think you know so much more than I?
Sorry...I'm not convinced.
John Higdon
Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> There's also iBiquity, which I haven't had time to tinker with. Since
> there are only 4 stations using it in the US (KROQ, WJLD, WOR, WRAL),
> methinks I can wait.
Which permutation of iBiguity? It has changed considerably over the past
year or so with its (reluctant) adoption of the AAC+ codec.
The earlier versions sounded like a bad webcast, IMHO.
Jeff Liebermann
<absolutel...@verislimesucks.com> wrote:
>In article <b9h910hi3f60f7b0t...@4ax.com>,
> Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
>> There's also iBiquity, which I haven't had time to tinker with. Since
>> there are only 4 stations using it in the US (KROQ, WJLD, WOR, WRAL),
>> methinks I can wait.
>Which permutation of iBiguity? It has changed considerably over the past
>year or so with its (reluctant) adoption of the AAC+ codec.
>The earlier versions sounded like a bad webcast, IMHO.
As I understand it, the original PAC codec was declared "defective"
due to "artifacts". The aacPlus codec was adopted to solve the
problem. It wasn't good enough, so they went to the HDC codec which
also carried a cheaper license fee. The NAB is recommending that the
codecs be left out of the spec as they apparently anticipate
additional changes. The OPTICODEC-PC MP4 codec is apparently the
current rising star. I guess there are others.
I've never heard any of these on the air, don't go to the shows,
haven't really followed the technology, and have no clue as to the
quality. I was just wondering if its a viable technology and suitable
competition for satellite radio.
John Higdon
Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> I've never heard any of these on the air, don't go to the shows,
> haven't really followed the technology, and have no clue as to the
> quality. I was just wondering if its a viable technology and suitable
> competition for satellite radio.
I've heard them all on the bench at Orban. The latest ones (at the FM
hybrid-mode rate of 64Kbps, same as satellite radio) sound nearly
transparent, meaning no artifacts can even be detected. At the rate of
96Kbps (hybrid-mode, no data or subchannel), I would imagine that they
are will nigh perfect. A lot of progress has been made in a very short
length of time.
The fly in the ointment is the "on the air" aspect. Once these bits have
been tossed to the ether, how it all sounds is unknown to me. How any of
these codecs behave in the environment of lost and corrupted data is now
the issue that determines suitability for prime time. We're still
talking about mid-band VHF which is subject to multipath, shadows, and
other gremlins that can play havoc with a data stream.
For what it's worth, I heard a magnificent codec running at 32Kbps. As
of the time I heard it (about two or three weeks ago), it was not yet
even announced to the world. It sounded fantastic. Maybe it was just the
realization that it was running at 32K, but it was pretty damned good.
Of course, that was on the bench with no data interference. It would
seem to be a natural for AM IBOC...if it can stand up to what MW
broadcast frequencies will do to it.
Radio can be a pill.
Jeff Liebermann
<absolutel...@verislimesucks.com> wrote:
>I've heard them all on the bench at Orban. The latest ones (at the FM
>hybrid-mode rate of 64Kbps, same as satellite radio) sound nearly
>transparent, meaning no artifacts can even be detected.
Orban is the company pushing the Mpeg4 Opticodec-PC over aacPlus.
>At the rate of
>96Kbps (hybrid-mode, no data or subchannel), I would imagine that they
>are will nigh perfect. A lot of progress has been made in a very short
>length of time.
Apples and oranges. At 96kbit/sec, your're talking about the FM
broadcast system, not the AM. At this time, I think only KROQ-FM in
Smog Angeles is doing digital FM. No clue which codec or system
they're using. Nothing on their web pile. FM digital is quite
different from AM digital stereo. You can do quite a bit more in FM's
200KHz channel, as compared to AM's 10KHz.
>The fly in the ointment is the "on the air" aspect. Once these bits have
>been tossed to the ether, how it all sounds is unknown to me. How any of
>these codecs behave in the environment of lost and corrupted data is now
>the issue that determines suitability for prime time. We're still
>talking about mid-band VHF which is subject to multipath, shadows, and
>other gremlins that can play havoc with a data stream.
Yep. The BER (bit error rate) of the Orban demos are probably
spectacularly good. Looking at the numbers from various listeners
using the European DRM system, 20dB S/N ratio is about typical for a
10E-5 BER.
http://www.tu-darmstadt.de/fb/et/uet/fguet/mitarbeiter/vf/DRM/performancereceiver.html
From my limited tinkering, better than 20dB is difficult in a real
world environment with an AM broadcast system.
>For what it's worth, I heard a magnificent codec running at 32Kbps. As
>of the time I heard it (about two or three weeks ago), it was not yet
>even announced to the world.
Well, even 32Kbits/sec is a stretch for AM broadcast. 11kbits/sec is
about what most AM broadcast data streams use. 14Kbits/sec seems to
be the upper limit. However, it's good to know that there's hope for
digital FM broadcast.
>It sounded fantastic. Maybe it was just the
>realization that it was running at 32K, but it was pretty damned good.
>Of course, that was on the bench with no data interference. It would
>seem to be a natural for AM IBOC...if it can stand up to what MW
>broadcast frequencies will do to it.
Ummm... I don't think the AM system can do 32Kbits/sec in a 10KHz
bandwidth. Are you sure this was for AM broadcast frequencies?
>Radio can be a pill.
Radio is magic.
Richard Steinfeld
> In article <iz2Rb.10821$XF6.2...@typhoon.sonic.net>,
> "Richard Steinfeld" <rgsteinBUT...@sonic.net>
wrote:
>
> > Bottom-feeding? Moonlighting? Whatever did I say that
made
> > you come to such conclusions?
>
> The way you snidely asked the question, as if I had made
up the
> appreviation to sound "in" or "cool" when it fact it was a
standard
> term, much like "FCC".
>
No. Not snide. A friendly tease.
> > John, perhaps you should think about the special
> > requirements of classical music audio and how they
relate to
> > AM transmission.
>
> [Whole big diatribe about the inferiority of AM
transmission, deleted.]
>
Your "diatribe" is my explanation.
> Oh, please. Been there, done that, have a closet full of
T-shirts. Not
> all classical listening is done with crackpot audio gear.
Some of it is
> done as background to other activities, and AM radio works
just fine for
> that. And when one drives in a car, the limited dynamic
range of AM is a
> feature, not a bug.
>
I agree. I said so in my post. In fact, there are times when
I find the range of the compact disk too much to handle in a
home livingroom. At those times, I wish for a compressor to
lower the fi.
Yeah, you may have been the engineer. But my ears picked up
that noise and distortion for years over many different
receivers. My bench technician, a classical instrumentalist,
couldn't stand the sound of your station: it wasn't just me.
> > Let's face it: the man transmitted crappy audio. KKHI,
> > although lower-powered and high-falutin, put out a
cleaner
> > signal. With audio quality like this pumped into the
air,
> > for a person who loves classical music, there's no
incentive
> > to invest in an audiophile FM tuner.
>
> If you think KKHI was the be-all and end-all of audio
quality, we don't
> have much to talk about.
>
No. I definitely could hear degredation in the KKHI signal,
too. But let's face it: KKHI spun records; your outfit
sounded like you were playing tapes of the records, and
certainly tapes of the announcements. That's a generation
of signal degredation, which is probably why KKHI sounded
cleaner.
> > You know, John, it might behoove you to have read what I
> > wrote before putting your condescending words into the
> > ether. You may have gleaned from what I initially wrote
that
> > I do indeed know something about the traditions of day
vs.
> > night power and licensing in AM broadcasting.
>
> Then why did you ask such a silly question in such a
condescending
> manner?
>
I'm sorry that you took it that way. I was kidding, tongue
in cheek. I wasn't intending to be condescending; I wanted
further explanation. I don't do well with acronyms: I forget
them when they aren't needed. And in the case of AM, I never
had need to know them in the first place. My station did not
simulcast. What I was prodding you for was to explain what
the acronyms mean for both myself or others who may have
tuned in.
> > Please remember this before you put down anyone else who
> > just may be an expert, someone who just might know a
hell of
> > a lot more than you do about the subject at hand.
>
> Actually, from your long diatribe, it would appear that I
was pretty
> much on the mark. What makes you think you know so much
more than I?
>
> Sorry...I'm not convinced.
Not a diatribe. John, you're really putting motives into my
mouth. I was giving a nice background, hopefully in a way
that a layperson could understand.
The issues may have to do with a different perspective. You
obviously have experience with the circuitry and the
components. This is arcane stuff. My own background is
stronger in the hearing side, as my training is in music and
musical instrument technology. I have a very highly trained
ear, which I've used in my own work. I may have been picking
up stuff that you weren't hearing. Some of the artifacts of
FM problems can be very strange and difficult to analyze in
the field. The experiences I've written about here, in fact,
happened. I didn't make this up. That awful sound was indeed
in the KDFC signal as I experienced it. I think that it did
improve in later years, but I don't recall this clearly.
My own experience has been that there is a difference in
orientation between radio technical people and audio
technical people. Although this is a generalization, I've
noticed that in the audio realm, there is great attention to
perfection in the rendition and purity of the musical
sounds. In broadcasting, the focus is typically on other
things, such as meeting FCC requirements, getting a big
polar graph to bring in the advertising bucks, and keeping
the bloody transmitter from shutting itself down while it is
warming up (a problem at WCRX): in other words, "Ohmygod!
Are we still on the air?????"
One thing that I noticed at WCRX, where there were two
subcarriers at work, was that the noise and distortion
problems would change depending upon a number of factors
similar to polarization, distance, etc. (I may be going too
far off topic now). For example, one of our announcers was
walking though his house listening to the station; he turned
a corner and suddenly, the main channel was replaced by the
audio from the subscriber channel (elevator music).
I wonder if I'm thinking mostly about the station during an
earlier period. I recall that one of the two stations
changed hands. Getting foggy with age, perhaps.
Richard
Philip J. Koenig
rgsteinBUT...@sonic.net (Richard Steinfeld) writes...
> "John Higdon" <absolutel...@verislimesucks.com> wrote
> in message
> news:absolutely.no.spam-6...@equine.announcetech.com...
> No. I definitely could hear degredation in the KKHI signal,
> too. But let's face it: KKHI spun records; your outfit
> sounded like you were playing tapes of the records, and
> certainly tapes of the announcements. That's a generation
> of signal degredation, which is probably why KKHI sounded
> cleaner.
Well John has recently made himself out (in this forum, in
another thread) to be a big fan of station automation - maybe
all that stuff was in fact taped. :-)
> My own experience has been that there is a difference in
> orientation between radio technical people and audio
> technical people. Although this is a generalization, I've
> noticed that in the audio realm, there is great attention to
> perfection in the rendition and purity of the musical
> sounds. In broadcasting, the focus is typically on other
> things, such as meeting FCC requirements, getting a big
> polar graph to bring in the advertising bucks, and keeping
> the bloody transmitter from shutting itself down while it is
> warming up (a problem at WCRX): in other words, "Ohmygod!
> Are we still on the air?????"
It seems that anyone with reasoning facilities could figure
out that radio has to contend with a big, giant unpredictable
set of variables (the airwaves, and the variables on the
receiving end) that the home audio (non radio) cosmos doesn't
have to even think about. I'd say that would be the main
reason why their focuses would be different, followed by the
commercial concerns.
After all, no audiophile would ever expect to hear truly
audiophile-quality audio from FM radio, except in extremely
rare circumstances. If some hifi equipment vendor, even at
the lowest end of the market, came out with a product that
had it's frequency response hit a brick wall at 15khz, they
would be heartily laughed at, for example.
> One thing that I noticed at WCRX, where there were two
> subcarriers at work, was that the noise and distortion
> problems would change depending upon a number of factors
> similar to polarization, distance, etc. (I may be going too
> far off topic now). For example, one of our announcers was
> walking though his house listening to the station; he turned
> a corner and suddenly, the main channel was replaced by the
> audio from the subscriber channel (elevator music).
Probably the very common phenomena of his body acting as an
antenna or a waveguide. I've known about this kind of thing
affecting radio reception since I was 10 or 12 years old, or
even earlier.
John Higdon
Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> >I've heard them all on the bench at Orban. The latest ones (at the FM
> >hybrid-mode rate of 64Kbps, same as satellite radio) sound nearly
> >transparent, meaning no artifacts can even be detected.
>
> Orban is the company pushing the Mpeg4 Opticodec-PC over aacPlus.
Bob and Greg are personal friends spanning three decades. I wasn't there
listening to some official demo. I got an honest sampling.
> Apples and oranges. At 96kbit/sec, your're talking about the FM
> broadcast system, not the AM. At this time, I think only KROQ-FM in
> Smog Angeles is doing digital FM. No clue which codec or system
> they're using. Nothing on their web pile. FM digital is quite
> different from AM digital stereo. You can do quite a bit more in FM's
> 200KHz channel, as compared to AM's 10KHz.
There are several stations in the Bay Area doing digital. KDFC is one
and I believe that 107.7 is another...at least judging from the grungy
adjacent-channel interference now being spewed. Other stations would
have been on by now, but the FCC threw a monkey wrench into the works
with a ruling on transmission methods. As far as the difference between
AM and FM is concerned, the matter is far more complex than a difference
in available bandwidth. The primary thing to note is what is called for
in the iBiquity specs, not the allowable occupied bandwidth of an FM or
AM channel. Consider what has to coexist in each channel in hybrid mode.
> From my limited tinkering, better than 20dB is difficult in a real
> world environment with an AM broadcast system.
Depends upon the dial position, class, day or night, expectations from
standard pattern coverage, etc., etc., etc. Too many variables to make a
blanket statement.
> Well, even 32Kbits/sec is a stretch for AM broadcast. 11kbits/sec is
> about what most AM broadcast data streams use. 14Kbits/sec seems to
> be the upper limit. However, it's good to know that there's hope for
> digital FM broadcast.
Take a look at the full iBiquity specification sometime. In full
digital, 32Kbps is expected to be the norm. I have the binders at home
rather than here at the office, so I'll check to be sure...but that's
how I remember it. For me, it is all academic; none of my AMs is
remotely considering going digital.
> >Radio can be a pill.
>
> Radio is magic.
I gave that notion up about thirty-five years ago.
Jeff Liebermann
<absolutel...@verislimesucks.com> wrote:
>Bob and Greg are personal friends spanning three decades. I wasn't there
>listening to some official demo. I got an honest sampling.
Was there a transmission imparement contraption available to reduce
the BER to realistic levels?
>There are several stations in the Bay Area doing digital. KDFC is one
>and I believe that 107.7 is another...at least judging from the grungy
>adjacent-channel interference now being spewed.
Cool. I'll play with it and see (er...hear) how it works. All my
tinkering has been with DRM. We'll see how iBiquity plays assuming I
can find software or the new TI DSP chip.
<http://focus.ti.com/docs/apps/catalog/general/applications.jhtml?templateId=938&path=templatedata/cm/general/data/audio_digrad_hdrad>
Transmission path to Ben Lomond should approximate a worst case
senario. Can I assume that the KDFC digital programming is classical
music?
107.7 is KSAN-FM. Susquahanna(?) also owns KFOG-FM 104.5 and 97.7. I
found a year old press release indicating that they've ordered Harris
transmitters and updgrades for HD broadcasting. Nothing since then.
>Take a look at the full iBiquity specification sometime. In full
>digital, 32Kbps is expected to be the norm.
Y'er right. All I could find was:
http://www.ibiquity.com/technology/pdf/Waveforms_AM.pdf
which indicates that the data rate is 20.2kbit/sec per channel or up
to 60.2kbit/sec aggregate data rate for all the channels (depending on
mode selected). Ok, I'm impressed. This I gotta see.
>> >Radio can be a pill.
>> Radio is magic.
>I gave that notion up about thirty-five years ago.
So much for me trying to be clever. Given a sufficiently excessive
level of complexity, the technology and specificiations start to
resemble magic. While I'm sure those immersed in the technology on a
day to day basis totally comprehend those technologies, the casual
armchair tinkerer, experimenter, and hacker, often finds the
technology somewhat incomprehensible and closely resembling magic.
Consistantly delivering a data rate of 6 times the occupied bandwidth,
over a very noisy channel, with a decent BER, is in my very humble
opinion, close to magic. Getting it approved by the FCC must also
have involved a magician or perhaps divine intervention. I've been
out of broadcasting since college daze (approx 1971), am somewhat
lost, and therefore tend to qualify the new digital technologies as
magic.
--
Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
John Higdon
Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> Was there a transmission imparement contraption available to reduce
> the BER to realistic levels?
Only what the network introduced. Realistically, no.
> Can I assume that the KDFC digital programming is classical
> music?
Yes, but beware. Last time I heard from Lou, the analog and digital were
not synchronized, negating the analog fallback. That may have been
corrected. Also, KDFC being an early adopter, it is hard to say what
codec is in play.
> 107.7 is KSAN-FM. Susquahanna(?) also owns KFOG-FM 104.5 and 97.7. I
> found a year old press release indicating that they've ordered Harris
> transmitters and updgrades for HD broadcasting. Nothing since then.
Susquehanna had ambitious plans for IBOC rollout. It isn't clear how and
if the FCC's decision on antennas may have affected those plans.
> >Take a look at the full iBiquity specification sometime. In full
> >digital, 32Kbps is expected to be the norm.
>
> Y'er right. All I could find was:
> http://www.ibiquity.com/technology/pdf/Waveforms_AM.pdf
> which indicates that the data rate is 20.2kbit/sec per channel or up
> to 60.2kbit/sec aggregate data rate for all the channels (depending on
> mode selected). Ok, I'm impressed. This I gotta see.
What I have is the package handed out at one of the dog-and-pony shows
for radio engineers. It is fairly complete, but now dated since I got it
over a year ago. I sort of depend on Bob and Greg for updates. None of
my stations (NONE!) has any digital plans at this time. The biggest
problem is transmitter floor space (no kidding!) and broadcast topology.
At present, there is no mechanism for implementing boosters, and my
stations have tons of them.
In the end, it all comes down to money. Vast quantities of money...for a
questionable return.
> Consistantly delivering a data rate of 6 times the occupied bandwidth,
> over a very noisy channel, with a decent BER, is in my very humble
> opinion, close to magic.
Perfectly doable if I remember my math. But, the real world does
frequently throw curves.
> Getting it approved by the FCC must also
> have involved a magician or perhaps divine intervention.
In this case: politics. The original codecs for IBOC were dogs, pure and
simple. What came out of them was dog excrement. The systems STILL
violate occupied-bandwidth rules and poke through the channel masks.
(Talk to some angry KPIG listeners sometime about how their favorite
station disappeared when a certain other station went digital.) Yet, the
FCC can be made to agree to anything if its arm is sufficiently twisted.
It's not like the old days.
It was heavy duty counter-politics that got new codecs introduced into
the picture. Besides the data streams, iBiguity had to be assured that
its licensing revenue stream would be unharmed. (Aside: I'm really
getting sick of all these parasites that have to get their licensing
fees...for doing nothing but handling licensing!)
> I've been
> out of broadcasting since college daze (approx 1971), am somewhat
> lost, and therefore tend to qualify the new digital technologies as
> magic.
Ah, nostalgia. I put KOME on the air back then (pretty much
single-handedly from an engineering standpoint), which began operation
February 1, 1971 at 6PM. A legendary station, now rapidly fading into
distant memory.
Richard Steinfeld
"Philip J. Koenig"
<See_email_@ddress_below.This_one_is.invalid> wrote in
message news:MPG.1a7feee7...@corp.supernews.com...
> In article <uqpRb.11039$XF6.2...@typhoon.sonic.net>,
> rgsteinBUT...@sonic.net (Richard Steinfeld)
writes...
>
> > "John Higdon" <absolutel...@verislimesucks.com>
wrote
> > in message
> >
news:absolutely.no.spam-6...@equine.announcetech.com...
>
>
> > No. I definitely could hear degredation in the KKHI
signal,
> > too. But let's face it: KKHI spun records; your outfit
> > sounded like you were playing tapes of the records, and
> > certainly tapes of the announcements. That's a
generation
> > of signal degredation, which is probably why KKHI
sounded
> > cleaner.
>
>
> Well John has recently made himself out (in this forum, in
> another thread) to be a big fan of station automation -
maybe
> all that stuff was in fact taped. :-)
>
I may be getting confused. Part of this was that at some
point, KDFC began really screwing around with the music. So,
whereas they'd been having tape and transmission distortion,
that was replaced (and perhaps this was when John came in,
though obviously not his fault) by interrupted music, parts
of symphonies, even parts of movements: instant death to
anyone who -listens- to classical music. At that point, I
tuned out permanently until after Bonneville Broadcasting
bought the channel.
>
> It seems that anyone with reasoning facilities could
figure
> out that radio has to contend with a big, giant
unpredictable
> set of variables (the airwaves, and the variables on the
> receiving end) that the home audio (non radio) cosmos
doesn't
> have to even think about. I'd say that would be the main
> reason why their focuses would be different, followed by
the
> commercial concerns.
>
Recording audio, too. I regard these two types of
engineering as almost mutually exclusive. I'll allow that
they both have transistors in common.
> After all, no audiophile would ever expect to hear truly
> audiophile-quality audio from FM radio, except in
extremely
> rare circumstances. If some hifi equipment vendor, even
at
> the lowest end of the market, came out with a product that
> had it's frequency response hit a brick wall at 15khz,
they
> would be heartily laughed at, for example.
>
Audiophiles, not truly correlating the characteristics of
real music with the reproduction, would undoubtedly find a
specification like this lacking. However, for a long time,
15khz was considered a very reasonable high end by
professionals. I worked at NY recording studios that could
not go higher. They also cut off at 30hz to kill the noise
of subway trains. The highest note on the piano is 4,400hz,
and there's very little musical energy up there that would
be missed by a person intent upon the music rather than the
fi. Further, the practical upper limit of cassette tape is
12khz. And if I recall, the original FM spec is to 15k. FM
broadcasting compromises the reproduction accuracy to push
the signal as far away as possible in order to encompass as
many advertising recipients as possible. Signal processors
carry out the task of manipulating, or cleverly
homogenizing, the sound so that it doesn't appear to suffer.
It is electronic slight-of-hand. I heard that one station in
Washington DC asked their listeners to choose whether they
wanted fidelity or distance. The listeners chose to take the
processors out of the chain. This may have been the only FM
station in the US that broadcast the best possible audio
obtainable with stereo.
I wonder if internet service has a practical equivalent. In
other words, I wonder if there are many times in which
performance doesn't matter that much. Hmmm.
>
> > One thing that I noticed at WCRX, where there were two
> > subcarriers at work, was that the noise and distortion
> > problems would change depending upon a number of factors
> > similar to polarization, distance, etc. (I may be going
too
> > far off topic now). For example, one of our announcers
was
> > walking though his house listening to the station; he
turned
> > a corner and suddenly, the main channel was replaced by
the
> > audio from the subscriber channel (elevator music).
>
>
> Probably the very common phenomena of his body acting as
an
> antenna or a waveguide. I've known about this kind of
thing
> affecting radio reception since I was 10 or 12 years old,
or
> even earlier.
>
Yes. But the effect here, I think, is compounded by the
interaction between the various subcarriers and their
individual content. Insanely complex, when you think about
it. Here in the Bay Area, you have to add in all the hills;
in NYC, it is all the buildings. Add in the fact that most
FM listeners don't use optimum roof antennas, but get the
signal over whip antennas of some sort. Insane.
Richard
Philip J. Koenig
rgsteinBUT...@sonic.net (Richard Steinfeld) writes...
>
> <See_email_@ddress_below.This_one_is.invalid> wrote in
> message news:MPG.1a7feee7...@corp.supernews.com...
> > audiophile-quality audio from FM radio, except in
> extremely
> > rare circumstances. If some hifi equipment vendor, even
> at
> > the lowest end of the market, came out with a product that
> > had it's frequency response hit a brick wall at 15khz,
> they
> > would be heartily laughed at, for example.
> >
>
> Audiophiles, not truly correlating the characteristics of
> real music with the reproduction,
That's a bit of an absurd presumption. Many "audiophiles" are
extremely astute about what does a better job of "reproducing
live music". Perhaps you have a term you prefer which you
don't consider universally derogatory. When I talk about
"audiophiles", I am using the term to refer to people who know
what they're talking about when it comes to audio quality. (I
specifically don't use "recording engineer", because I've known
or known of many of them that are downright hacks with a tin
ear)
> would undoubtedly find a
> specification like this lacking. However, for a long time,
> 15khz was considered a very reasonable high end by
> professionals. I worked at NY recording studios that could
> not go higher. They also cut off at 30hz to kill the noise
> of subway trains. The highest note on the piano is 4,400hz,
> and there's very little musical energy up there that would
> be missed by a person intent upon the music rather than the
> fi.
This is like designing a car that will only go 55mph on a good
day because "that's as high as the speed limit". (well, it used
to be) There are many reasons to not design equipment to the
lowest common denominator, and every hack in the world likes to
justify junk technology by making such claims -- until they're
trying to promote some technology that has the ability to actually
reproduce the full audible spectrum.
Most people, given the choice, and given how easy it is to accomplish
from a technical standpoint these days, prefer to buy equipment that
doesn't have a permanent handicap -- even if you're not sure you can
tell the difference between something that rolls off at 15k as opposed
to 20k, why would anyone voluntarily opt for such things when it's
trivial to support the full bandwidth? And I suppose you will tell us
that all the companies promoting, and audio critics raving about, new
digital formats such as DVD-Audio and SACD whose primary claim-to-fame
are "bandwidth beyond the audio band". There are all sorts of simpleton
engineers who will boldly proclaim that Nyquist has made the idea of
sampling anything with a rate exceeding 2x the bandwidth of the signal
a waste of time, but time and time again people hear improvements in
sound reproduction when these techniques are used.
> Further, the practical upper limit of cassette tape is
> 12khz.
Tell that to Nakamichi who started selling decks flat to 20khz
back in the '70s. (and the tape that they had to use to do it
was far inferior to what is available today)
> And if I recall, the original FM spec is to 15k.
That is precisely why I mentioned that figure.
> FM
> broadcasting compromises the reproduction accuracy to push
> the signal as far away as possible in order to encompass as
> many advertising recipients as possible. Signal processors
> carry out the task of manipulating, or cleverly
> homogenizing, the sound so that it doesn't appear to suffer.
It's amazing how far you will go to justify your opinion about
the "acceptability" of losing half the last audible octave, when
we were just treated to a long-winded diatribe about how completely
crappy certain local FM stations sounded to you - when others
apparently thought they were just fine.
(Personally I never really paid much attention because I've rarely,
even with pretty expensive tuners, lived in a location that could
consistently receive a good enough quality signal of any local
classical station to be motivated to listen to it with "golden ear"
expectations.
Once upon a time James Gabbert made a big to-do here in the BA about
K-101's audio quality, and used to have a certain showcase program
where he tried to push the quality envelope. I'm not sure any other
local station has ever made any similiar effort. And if a classical
station with halfway decent sound-quality plays nothing but boring
hackneyed populist pieces that everyone's heard 1,000 times already,
what would be the point anyway, except to use it as background music
in a department store or something?
> It is electronic slight-of-hand. I heard that one station in
> Washington DC asked their listeners to choose whether they
> wanted fidelity or distance. The listeners chose to take the
> processors out of the chain. This may have been the only FM
> station in the US that broadcast the best possible audio
> obtainable with stereo.
And I presume all those people were living in some flatland
too. Ever try to get good off-the-air FM reception in 90%
of San Francisco, or the East Bay, from most of the worthwhile
stations that are broadcasting from the other side of the
Oakland hills?
> I wonder if internet service has a practical equivalent. In
> other words, I wonder if there are many times in which
> performance doesn't matter that much. Hmmm.
Undoubtedly. If quality of service were that important to the
average consumer, companies like Comcast and AOL would have
gone out of business years ago.
Yep.
Now one more thing: what kind of newsreader is it that mangles
attributions as badly as the one you're using? What is the
linewrap set to - 40 characters?
(Ah.. nevermind, answered my own question: Outlook Express. Why
am I not surprised.. :-)
Jeff Liebermann
<See_email_@ddress_below.This_one_is.invalid> wrote:
>(I specifically don't use "recording engineer", because I've known
>or known of many of them that are downright hacks with a tin
>ear)
Yep. You get that way after listening to a lifetime of recording
sessions. However, it will only get worse. MP3's and DVD's
apparently cause hearing damage:
http://www.informatik.fh-hamburg.de/~windle_c/Logologie/MP3-Gefahr/MP3-risk.html
which insures that all recording engineers will soon be deaf.
John Higdon
Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> Yep. You get that way after listening to a lifetime of recording
> sessions. However, it will only get worse. MP3's and DVD's
> apparently cause hearing damage:
> http://www.informatik.fh-hamburg.de/~windle_c/Logologie/MP3-Gefahr/MP3-risk.ht
> ml
> which insures that all recording engineers will soon be deaf.
Back when we were still debating whether uncompressed 16 bit, 44.1K
sample rate was "good enough" to be considered "high fidelity", some of
the radio engineers joked about how digital audio would eventually cause
people's arms to fall off.
Thanks for that reference. It is the liveliest piece of hocus-pocus
nonsense I have seen on the web in months. If we had had the web at the
beginning of the 20th century, more people would have learned that going
faster than 35MPH would take one's breath away!
Jeff Liebermann
<absolutel...@verislimesucks.com> wrote:
>In article <qnef1056clhnh81n6...@4ax.com>,
> Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
>
>> Yep. You get that way after listening to a lifetime of recording
>> sessions. However, it will only get worse. MP3's and DVD's
>> apparently cause hearing damage:
>> http://www.informatik.fh-hamburg.de/~windle_c/Logologie/MP3-Gefahr/MP3-risk.ht
>> ml
>> which insures that all recording engineers will soon be deaf.
>Back when we were still debating whether uncompressed 16 bit, 44.1K
>sample rate was "good enough" to be considered "high fidelity", some of
>the radio engineers joked about how digital audio would eventually cause
>people's arms to fall off.
I vaguely recall the serious discussions in the late 1970's claiming
quadraphonic speaker arrangements might induce disorientation or
vertigo, making the manufacturers legally liable for any subsequent
injuries.
>Thanks for that reference.
Please thank Philip Koenig, who first brought it to my attention.
>It is the liveliest piece of hocus-pocus
>nonsense I have seen on the web in months. If we had had the web at the
>beginning of the 20th century, more people would have learned that going
>faster than 35MPH would take one's breath away!
I don't know enough about how the human ear works to pass judgement on
the claims. I do tend to simulate deafness when listening to what
passes for popular music, during commercials, and while talking on my
cell phone. However, these effects might be from causes other than
listening to perceptually compressed music.
To be sure, you can sorta test your hearing online. See:
http://www.freehearingtest.com/test.shtml
http://www.entnet.org/healthinfo/hearing/hearing_test.cfm
http://weinstein.cncfamily.com/AAI/index.html
http://www.azhearing.com/heartest2.htm
If you don't hear anything, you're either going deaf or your Windoze
sound driver is broken.
My favorite (spare time) web pile is:
http://www.junkscience.com
Headaches from Cell Phones:
http://www.junkscience.com/news/headache.htm
Researchers find differences in inner ear structure in gays:
http://www.junkscience.com/news/gayears.htm
Steve Pope
>Yep. You get that way after listening to a lifetime of recording
>sessions. However, it will only get worse. MP3's and DVD's
>apparently cause hearing damage:
>http://www.informatik.fh-hamburg.de/~windle_c/Logologie/MP3-Gefahr/MP3-risk.html
>which insures that all recording engineers will soon be deaf.
Yeah. I've been saying this for the last 15 years
but nobody will listen. Like, they're not hearing me
or something. Like, they're deaf.
Compressed audio is such a bad idea -- from Dolby B onward.
Steve
ka...@rahul.net
<je...@comix.santa-cruz.ca.us> wrote:
>On Wed, 28 Jan 2004 03:37:13 -0800, Philip J. Koenig
><See_email_@ddress_below.This_one_is.invalid> wrote:
>>(I specifically don't use "recording engineer", because I've known
>>or known of many of them that are downright hacks with a tin
>>ear)
>
>Yep. You get that way after listening to a lifetime of recording
>sessions. However, it will only get worse. MP3's and DVD's
>apparently cause hearing damage:
>http://www.informatik.fh-hamburg.de/~windle_c/Logologie/MP3-Gefahr/MP3-risk.html
>which insures that all recording engineers will soon be deaf.
By this guy's logic, all of us who grew up listening to radio
in the 40s and 50s, before general use of hi-fi techniques, should
have been deaf by the age of fifteen.
ka...@rahul.net
> http://www.freehearingtest.com/test.shtml
> http://www.entnet.org/healthinfo/hearing/hearing_test.cfm
> http://weinstein.cncfamily.com/AAI/index.html
> http://www.azhearing.com/heartest2.htm
>If you don't hear anything, you're either going deaf or your Windoze
>sound driver is broken.
Great -- both of my ears rebooted in the middle of the test.
:-)
Jeff Liebermann
Chuckle. I've been pounding on my Korg DSS-1 keyboard synthesizer for
about 13 years using the same pair of earphones. Over the years, the
volume control has been slowly creeping up from mid scale, to near
full blast. If I placed the volume control in the same position that
worked well about 8 years ago, the volume was far too low. I was
getting worried that my hearing was going down the drain, so I
arranged for an audiometric hearing test. I'm "normal" for my age.
Eventually, my paranoia was relieved when the synthesizers driver
amplifier finally blew up. 8 dried out electrolytic cazapitors later,
the volume control was back in its original position. Then, I stopped
worrying about hearing loss.
--
Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
John Higdon
ka...@rahul.net wrote:
> By this guy's logic, all of us who grew up listening to radio
> in the 40s and 50s, before general use of hi-fi techniques, should
> have been deaf by the age of fifteen.
That's why selection of just the right cactus needles was so important.
Philip J. Koenig
cruz.ca.us (Jeff Liebermann) writes...
> On Wed, 28 Jan 2004 06:49:42 -0800, John Higdon
> <absolutel...@verislimesucks.com> wrote:
>
> >In article <qnef1056clhnh81n6...@4ax.com>,
> > Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> >
> >> Yep. You get that way after listening to a lifetime of recording
> >> sessions. However, it will only get worse. MP3's and DVD's
> >> apparently cause hearing damage:
> >> http://www.informatik.fh-hamburg.de/~windle_c/Logologie/MP3-Gefahr/MP3-risk.ht
> >> ml
> >> which insures that all recording engineers will soon be deaf.
>
> >Back when we were still debating whether uncompressed 16 bit, 44.1K
> >sample rate was "good enough" to be considered "high fidelity", some of
> >the radio engineers joked about how digital audio would eventually cause
> >people's arms to fall off.
>
> I vaguely recall the serious discussions in the late 1970's claiming
> quadraphonic speaker arrangements might induce disorientation or
> vertigo, making the manufacturers legally liable for any subsequent
> injuries.
>
> >Thanks for that reference.
>
> Please thank Philip Koenig, who first brought it to my attention.
Did I? <blush>
> >It is the liveliest piece of hocus-pocus
> >nonsense I have seen on the web in months. If we had had the web at the
> >beginning of the 20th century, more people would have learned that going
> >faster than 35MPH would take one's breath away!
>
> I don't know enough about how the human ear works to pass judgement on
> the claims. I do tend to simulate deafness when listening to what
> passes for popular music, during commercials, and while talking on my
> cell phone. However, these effects might be from causes other than
> listening to perceptually compressed music.
Well then, since we're on the subject..
Mark Anstendig was a regular at a hifi shop I used to work at, and
he has some "interesting" ideas about the impact that various
vibrations (including audio) have on human beings. You may find
this stuff either fascinating, or entertaining. :-)
Philip J. Koenig
cruz.ca.us (Jeff Liebermann) writes...
> On Thu, 29 Jan 2004 08:33:09 GMT, ka...@rahul.net wrote:
>
> >>To be sure, you can sorta test your hearing online. See:
> >> http://www.freehearingtest.com/test.shtml
> >> http://www.entnet.org/healthinfo/hearing/hearing_test.cfm
> >> http://weinstein.cncfamily.com/AAI/index.html
> >> http://www.azhearing.com/heartest2.htm
> >>If you don't hear anything, you're either going deaf or your Windoze
> >>sound driver is broken.
>
> > Great -- both of my ears rebooted in the middle of the test.
> >:-)
>
> Chuckle. I've been pounding on my Korg DSS-1 keyboard synthesizer for
> about 13 years using the same pair of earphones. Over the years, the
> volume control has been slowly creeping up from mid scale, to near
> full blast. If I placed the volume control in the same position that
> worked well about 8 years ago, the volume was far too low. I was
> getting worried that my hearing was going down the drain, so I
> arranged for an audiometric hearing test. I'm "normal" for my age.
>
> Eventually, my paranoia was relieved when the synthesizers driver
> amplifier finally blew up. 8 dried out electrolytic cazapitors later,
> the volume control was back in its original position. Then, I stopped
> worrying about hearing loss.
In the true entrepreneurial spirit, I therefore hereby recommend
bringing a product to market, whose marketing material touts its
remarkable ability to correct hearing loss.
The basic architecture would consist of an internally programmed
stereo attenuator, with input and output RCA jacks designed to be
inserted into your amplifier's tape loop. When first installed,
the unit is activated by either switch or installation of batteries,
etc. Over a certain carefully chosen period of time, the internal
attenuators progressively increase their attenuation level. This
period is referred to in the manual as the "conditioning and
optimization phase".
After the requisite timeframe has elapsed, an indicator on the box
lights up, according to the manual, "indicating that the proper
syncronization and conditioning has been achieved for the specific
listener's ear characteristics". Then the listener is instructed
to depress the clearly labeled "defenestration" button, whereupon
the audio jumps up about 30 db, and another disgustingly bright
LED starts ferociously flashing, indicating another listenener
has been cured of debilitating hearing-loss. :-)
Philip J. Koenig
rgsteinBUT...@sonic.net (Richard Steinfeld) writes...
> FM
> broadcasting compromises the reproduction accuracy to push
> the signal as far away as possible in order to encompass as
> many advertising recipients as possible. Signal processors
> carry out the task of manipulating, or cleverly
> homogenizing, the sound so that it doesn't appear to suffer.
> It is electronic slight-of-hand. I heard that one station in
> Washington DC asked their listeners to choose whether they
> wanted fidelity or distance. The listeners chose to take the
> processors out of the chain. This may have been the only FM
> station in the US that broadcast the best possible audio
> obtainable with stereo.
Some interesting webpages for uber-FM-tuner geeks:
http://www.fmtunerinfo.com/index.html
http://www.audiocircuit.com/9130-tuner-circuit/9130IMAI.htm
John R Pierce
<See_email_@ddress_below.This_one_is.invalid> wrote:
>Some interesting webpages for uber-FM-tuner geeks:
I have to say that out of all the FM tuners I've listened to, my Adcom
GFT555-II (I think thats the right number) sounds head and shoulders above
the rest of more mundane things. It sounds especially good on this live
pirate FM broadcast at a particular music festival I frequent, which uses
minimal compression, and a wider than normal modulation (its so far out in
the boonies the 10 watts or so transmitter power isn't going to impinge on
anything).
John Higdon
John R Pierce <sp...@is.invalid> wrote:
> I have to say that out of all the FM tuners I've listened to, my Adcom
> GFT555-II (I think thats the right number) sounds head and shoulders above
> the rest of more mundane things. It sounds especially good on this live
> pirate FM broadcast at a particular music festival I frequent, which uses
> minimal compression, and a wider than normal modulation (its so far out in
> the boonies the 10 watts or so transmitter power isn't going to impinge on
> anything).
Yes, signal processing is a bitch. Without it, FM audio is awesome.
Ironically, those who rail hardest against the processing that
commercial and non-commercial stations do (necessary to keep their
emissions inside their respective channels) are among the biggest
advocates of plopping MORE stations into the congestion.
While I haven't tested the tuner you mention above, it has been my
experience that by and large, tuners have two major problems: deviation
from the 75 microsecond deemphasis curve (by several db or better) and a
general high-end rolloff. This observation applies to all tuners that
I've tested so far, including the most expensive and crackpot-approved.
I guess this is why radio stations still depend on their type-accepted
modulation monitors (which must meet a tight spec for type-acceptance)
to actually hear what the station sounds like.
Well, I'm off to Ham Radio Outlet to buy a 2-meter mobile antenna to
replace the one that broke off the mobile studio (for the wireless
mics). All these years and we STILL have to improvise with makeshift
solutions!
Philip J. Koenig
absolutel...@verislimesucks.com (John Higdon) writes...
> While I haven't tested the tuner you mention above, it has been my
> experience that by and large, tuners have two major problems: deviation
> from the 75 microsecond deemphasis curve (by several db or better) and a
> general high-end rolloff. This observation applies to all tuners that
> I've tested so far, including the most expensive and crackpot-approved.
What kind of rolloff are you talking about?
Given the effect of pilot tone creeping into the output (ie,
causing lots of problems with tape decks among other things),
I can understand why various tuner vendors are more worried
about adequate suppression of that tone in the audio signal
over the last iota of high-frequency response, particularly
since no one conventionally expects anything above 15khz
using the traditional FM broadcast standard anyway.
Back in the olden days of primitive filters, it may have been
a challenge to notch out that signal without a certain amount
of rolloff prior to the subcarrier frequency, but that shouldn't
be a big issue with modern filters. (in theory anyway)
Then again, maybe these audio designers aren't fans of
"brickwall" filters for other sonic reasons. (phase shift, etc.)
And here is your friend Bob Orban claiming there isn't anything
interesting above 15khz anyway:
http://www.broadcast.net/pipermail/radio-tech/2002-September/027470.html
Tangentially: what "shoestring broadcaster" is the guy in the
page below (story at top) referring to? (I presume you know
all about this)
http://home.earthlink.net/~srw-swling/glenn.htm
Jeff Liebermann
<absolutel...@verislimesucks.com> wrote:
>While I haven't tested the tuner you mention above, it has been my
>experience that by and large, tuners have two major problems: deviation
>from the 75 microsecond deemphasis curve (by several db or better) and a
>general high-end rolloff. This observation applies to all tuners that
>I've tested so far, including the most expensive and crackpot-approved.
I don't think it's the de-emphasis network that's causing the rolloff.
To keep the rolloff reasonably sane, the 10.7Mhz IF filter has to be
considerably wider than the 200KHz channel spaceing. The group delay
(phase errors) at the ends of the bandpass are well into the adjacent
channels. You get good inband phase linearity, a fairly straight line
on the -6dB/octave de-emphasis curve, and absolutely miserable
adjacent channel rejection. That's that the FCC assigns FM stations
on alternate 200KHz channel assignments. It's also why tuner
performance does not specify adjacent channel rejection, but instead
specifies alternate channel rejection. Tuners that try to improve on
the adjacent channel rejection with more complex IF filtering, usually
end up with some droop at the band edges resulting in a sagging
de-emphasis curve.
I've tinkered with a really cool SDR (software defined radio) board,
using brick wall IF filtering, that doesn't have the adjacent channel
vs frequency response tradeoff. Phase linearity is perfect to the
band edges. Don't ask about baseline noise level as clock leaks are
still a problem. Of course, it's not ready for consumer prime time
yet.
http://www.gnu.org/software/gnuradio/gnuradio.html
Note that I'm talking about the SDF that digitizes a big chunk of the
FM band and does everything from filtering to demodulation on a
dedicated DSP card and NOT one that digitizes the 10.7MHz coming out
of the IF of a tuner.
Here's another DSP FM receiver based on an iPaq running Linux:
http://www.linuxdevices.com/news/NS7890250038.html
>I guess this is why radio stations still depend on their type-accepted
>modulation monitors (which must meet a tight spec for type-acceptance)
>to actually hear what the station sounds like.
Naw. It's because test equipment measurements are repeatable, while
the human ear is subject to considerable variations in quality,
sensitivity, and objectivity.
>Well, I'm off to Ham Radio Outlet to buy a 2-meter mobile antenna to
>replace the one that broke off the mobile studio (for the wireless
>mics). All these years and we STILL have to improvise with makeshift
>solutions!
When I was doing land mobile, the most common repairs were to mobile
antennas and microphones. I suggest stocking some spares. If that's
impossible, visit a hobby shop or welding supply store, and ask for
"music wire".
Eric Weaver
> I've tinkered with a really cool SDR (software defined radio) board,
> using brick wall IF filtering, that doesn't have the adjacent channel
> vs frequency response tradeoff. Phase linearity is perfect to the
> band edges. Don't ask about baseline noise level as clock leaks are
> still a problem. Of course, it's not ready for consumer prime time
> yet.
Another issue is that when you brick-wall filter the IF to 200 KHz you get
higher distortion. In frequency domain, you're lopping off some outer
sidebands; in time domain, you're limiting the rate of frequency change.
Plus you can never completely get rid of the outer sidebands of the
first-adjacent signal.
No free lunch where there's a first-adjacent signal - you pay with
interference or distortion.
John H, I recommend to just go for the $17 MFJ mag-mount dual-bander. Works
for wireless mike on 170 and for UHF remote pickup band. They're cheap enough
you can buy a bunch for spares.
John Higdon
Eric Weaver <we...@sigma.net> wrote:
> John H, I recommend to just go for the $17 MFJ mag-mount dual-bander. Works
> for wireless mike on 170 and for UHF remote pickup band. They're cheap
> enough
> you can buy a bunch for spares.
You're not going to believe this, but that's exactly what I ended up
doing!
John Higdon
Javier Henderson <jav...@KJSL.COM> wrote:
> John Higdon <absolutel...@verislimesucks.com> writes:
>
> > Well, I'm off to Ham Radio Outlet to buy a 2-meter mobile antenna to
> > replace the one that broke off the mobile studio (for the wireless
> > mics). All these years and we STILL have to improvise with makeshift
> > solutions!
>
> Tsk, tsk. Improvising would be using a wire coat hanger. You're
> going for the prosumer solution!
That sort of repair is reserved for transmitters. You have no idea how
much coat hanger wire and Tap Plastics material found its way into the
first KOME transmitter. I became very familiar with the name "Devcon".
I'm in the big leagues now; I get to purchase at a ham store!
Eric Weaver
> In article <40195a58$1...@news.announcetech.com>,
> Eric Weaver <we...@sigma.net> wrote:
>
>
>>John H, I recommend to just go for the $17 MFJ mag-mount dual-bander. Works
>>for wireless mike on 170 and for UHF remote pickup band. They're cheap
>>enough
>>you can buy a bunch for spares.
>
>
> You're not going to believe this, but that's exactly what I ended up
> doing!
>
Great minds run in the same gutter...
ObInternet: My SBC year will be up soon, and I may be ready to "rough it" for
a week and a half and switch to Sonic.
ka...@rahul.net
<See_email_@ddress_below.This_one_is.invalid> wrote:
>Well then, since we're on the subject..
>
>Mark Anstendig was a regular at a hifi shop I used to work at, and
>he has some "interesting" ideas about the impact that various
>vibrations (including audio) have on human beings. You may find
>this stuff either fascinating, or entertaining. :-)
>
>http://www.anstendig.org/
I gotta say he has some interesting entries in the his table
of contents:
Improving the Quality of the Vibrational Influences in your Life
At first glance I thoought he'd hired Susie Bright as a
writer. :-)
ka...@rahul.net
wrote:
>It sounds especially good on this live
>pirate FM broadcast at a particular music festival I frequent, which uses
>minimal compression, and a wider than normal modulation (its so far out in
>the boonies the 10 watts or so transmitter power isn't going to impinge on
>anything).
Pirate??? I bet it'll impinge on Slade if he sees this
posting. :-)
Jeff Liebermann
>Mark Anstendig was a regular at a hifi shop I used to work at, and
>he has some "interesting" ideas about the impact that various
>vibrations (including audio) have on human beings. You may find
>this stuff either fascinating, or entertaining. :-)
>http://www.anstendig.org/
Oh groan. Not the full body experience theory, again. Way back in
the early 1960's, there was what I suspected was an April Fools joke
in what I guess(tm) was the Journal of the Audio Engineering Society.
It claimed that the only way to truely experience high fidelity sound
was to "immerse" the listener in the sound "experience". The method
chosen was to submerge the listener in a swimming pool, and pump sound
at them from all directions. For a more realistic environment,
sitting in a water filled chair was suggested. I'm still not sure if
it was a joke or for real, but variations on the full body experience
theory have been epidemic ever since. In the 70's, it was
quadraphonic sound, which sometimes placed the listener in the middle
of the orchestra, a rather location. Independent bass "floor shakers"
were invented to give your feet a musical massage and to piss of the
neighbors. Now daze, "it's the beat" which translates into a +30dB
gain peak at 20Hz giving the entire neighborhood the benifits of a
full body boom...boom...boom...boom sound (usually with the added
enjoyment of the distortion caused by the speaker coil hitting the end
of travel).
Obviously, I'm not an audiophile or hi-fi-natic. A fairly
conservative selection of electronics and speakers will yield music
that is adequate for 95% of the potential audience and 95% of the
musical selections available. For the remaining 5%, no amount of
money will buy perfection.
Drivel: Back in the 1960's, I built a phoney "Ambience and Presence"
meter. I sent a press release and photo to Radio Electronics Mag who
published it as a product release. I got quite a few queries, mostly
from authors, reviewers, and labs, wanting to know how I had
successfully measured something that was universally considered an
intangible. After about 5 years, I figured it was safely forgotten,
when I was confronted with the press release during a job interview.
It seems that engineers and audiophiles have longer memories for jokes
and humor, than more serious topics.
--
Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
Philip J. Koenig
Philip J. Koenig
cruz.ca.us (Jeff Liebermann) writes...
> On Thu, 29 Jan 2004 07:47:05 -0800, Philip J. Koenig
>
> >Mark Anstendig was a regular at a hifi shop I used to work at, and
> >he has some "interesting" ideas about the impact that various
> >vibrations (including audio) have on human beings. You may find
> >this stuff either fascinating, or entertaining. :-)
> >http://www.anstendig.org/
>
> Oh groan. Not the full body experience theory, again. Way back in
> the early 1960's, there was what I suspected was an April Fools joke
> in what I guess(tm) was the Journal of the Audio Engineering Society.
> It claimed that the only way to truely experience high fidelity sound
> was to "immerse" the listener in the sound "experience". The method
> chosen was to submerge the listener in a swimming pool, and pump sound
> at them from all directions. For a more realistic environment,
> sitting in a water filled chair was suggested. I'm still not sure if
> it was a joke or for real, but variations on the full body experience
> theory have been epidemic ever since. In the 70's, it was
> quadraphonic sound, which sometimes placed the listener in the middle
> of the orchestra, a rather location.
Well there are unquestionably differences in the experience of music
when the method of delivery changes. Listening to organ music with
lots of low frequency content on headphones, for example, is a
distinctly different experience than listening to it through speakers
in a room. (or live in a church or concert hall, for that matter)
To me it's rather obvious that the lack of sound waves making your
shirt-sleeves flutter in the wind is the major differentiating factor.
Now you or I may even prefer the headphone experience for various
reasons, but you can't deny that the visceral experience is somewhat
different. (even if the frequency response is equivalent)
On the other side of the coin, back in the '70s, we (or at least I)
discovered how cool some albums sounded when played in headphones,
and it really wasn't completely duplicable when playing them over
speakers.
> Independent bass "floor shakers"
> were invented to give your feet a musical massage and to piss of the
> neighbors. Now daze, "it's the beat" which translates into a +30dB
> gain peak at 20Hz giving the entire neighborhood the benifits of a
> full body boom...boom...boom...boom sound (usually with the added
> enjoyment of the distortion caused by the speaker coil hitting the end
> of travel).
Sometimes I have fantasies of outlawing "boom cars"..
> Obviously, I'm not an audiophile or hi-fi-natic. A fairly
> conservative selection of electronics and speakers will yield music
> that is adequate for 95% of the potential audience and 95% of the
> musical selections available. For the remaining 5%, no amount of
> money will buy perfection.
>
> Drivel: Back in the 1960's, I built a phoney "Ambience and Presence"
> meter. I sent a press release and photo to Radio Electronics Mag who
> published it as a product release. I got quite a few queries, mostly
> from authors, reviewers, and labs, wanting to know how I had
> successfully measured something that was universally considered an
> intangible. After about 5 years, I figured it was safely forgotten,
> when I was confronted with the press release during a job interview.
> It seems that engineers and audiophiles have longer memories for jokes
> and humor, than more serious topics.
Funny thing is, lots of that stuff has now been quantified and
reproduced. Now engineers use such signal processing tricks as
a standard part of their repertoire now. Matter of fact, many
modern mass-market PC sound-cards widely exploit these things
and have tweakable settings for all that stuff.
(By the way, if anyone happens to be looking for the famous Yamaha
"DSP-100" "Digital Soundfield Processor", the device that basically
put that whole product category on the map for home hifi purposes,
I've got one for sale. :-)
Niggle: the DSP-100 is more of an additive device than an "ambience
recovery" device. The latter is better represented by another well-
known product that I also own, the Lexicon CP-1+, which is not yet
for sale..
ka...@rahul.net
<je...@comix.santa-cruz.ca.us> wrote:
>
>Obviously, I'm not an audiophile or hi-fi-natic. A fairly
>conservative selection of electronics and speakers will yield music
>that is adequate for 95% of the potential audience and 95% of the
>musical selections available. For the remaining 5%, no amount of
>money will buy perfection.
>
Funny thing -- I've been saying the same kind of thing for
years about OSes. :-)
John R Pierce
<See_email_@ddress_below.This_one_is.invalid> wrote:
>Sometimes I have fantasies of outlawing "boom cars"..
most every town has noise laws, its often something like 45dBA from 50
feet away... boom cars easily exceed this by several orders of magnitude,
heck, cranking up the small aftermarket stereo in my old VOLVO probably
exceeds it if the windows are down. Its hardly ever enforced.
Jeff Liebermann
wrote:
>Jeff Liebermann wrote:
>
>> I've tinkered with a really cool SDR (software defined radio) board,
>> using brick wall IF filtering, that doesn't have the adjacent channel
>> vs frequency response tradeoff. Phase linearity is perfect to the
>> band edges. Don't ask about baseline noise level as clock leaks are
>> still a problem. Of course, it's not ready for consumer prime time
>> yet.
>Another issue is that when you brick-wall filter the IF to 200 KHz you get
>higher distortion. In frequency domain, you're lopping off some outer
>sidebands; in time domain, you're limiting the rate of frequency change.
Yep. However, the effect is most pronounced at the higher audio
frequencies. Fortunately, the harmonics of these frequencies are well
out of the bandpass and a simple audio low pass filter will take them
out. Also, the de-emphasis network insures that the higher
frequencies and its associated higher frequency harmonics are greatly
reduced when compared to the lower audio frequencies. However, I do
agree. Excessive number of poles in the brick wall filter creates
more problems than it solves. I'm not sure how to optimize the number
of poles but the sample FM broadcast digital filter used only about 24
poles.
>Plus you can never completely get rid of the outer sidebands of the
>first-adjacent signal.
Sure. Bessel functions insist that sidebands blunder outside the
bandpass. The theory is that FM capture effect takes care of most
adjacent channel interference. It's not much of a problem for home
listeners that can hear only a few stations. It's really a PITA on
mountain top CATV headend sites can hear hundreds of stations. Big
directional antennas with low side lobes are the only answer. Tricky
demodulators like a pulse counting discriminator also helps reject the
junk and provide super discriminator linearity.
>No free lunch where there's a first-adjacent signal - you pay with
>interference or distortion.
I'll take the distortion as it's most out-of-band harmonics that can
be easily removed with a simple audio low pass filter.
>John H, I recommend to just go for the $17 MFJ mag-mount dual-bander. Works
>for wireless mike on 170 and for UHF remote pickup band. They're cheap enough
>you can buy a bunch for spares.
Yep... It's NBC (nothing but the cheapest).
I prefer the NMO mounts. Easy to mount. A .45 caliber slug makes
about the right size hole.
ab...@mix.com
> Commercial popular music, which dominates
> the AM spectrum, has a limited dynamic range and usually a
> limited frequency range. That's just the nature of it. The
> high-frequency limit is governed by the actual carrier wave
> frequency. Thus, a station at the bottom of the AM dial has
> a limit that would intrude on the requirements, let's say,
> of jazz. A station toward the upper end of the AM dial can
> actually do a fairly good job of handling the frequency
> ranges of all types of music.
This is utter nonsense. The only real difference is lower
frequencies propagate farther, so stations on those channels
have better coverage for a given amount of radiated energy
and ground conductivity.
> A symphony can have a dynamic range that taxes the abilities
> of fine audiophile equipment to reproduce accurately.
Again, more nonsense. The ambient noise level of the listening
environment would undoubtly be the limiting factor here. The
typical audiophile has, if anything, _better_ gear than what was
used to make the typical recording, not to mention broadcast it.
Billy Y..
John Higdon
> Richard Steinfeld <rgsteinBUT...@sonic.net> writes:
>
> > Commercial popular music, which dominates
> > the AM spectrum, has a limited dynamic range and usually a
> > limited frequency range. That's just the nature of it. The
> > high-frequency limit is governed by the actual carrier wave
> > frequency. Thus, a station at the bottom of the AM dial has
> > a limit that would intrude on the requirements, let's say,
> > of jazz. A station toward the upper end of the AM dial can
> > actually do a fairly good job of handling the frequency
> > ranges of all types of music.
>
> This is utter nonsense. The only real difference is lower
> frequencies propagate farther, so stations on those channels
> have better coverage for a given amount of radiated energy
> and ground conductivity.
Indeed. Stations at the low end of the band operate within the very same
NRSC mask that the stations up at the top have to fit in. Dial position
has absolutely nothing to do with available bandwidth. I failed to see
this bit-o-nonsense the first time around...probably because the BS
level was so high in general I tuned out before I got there!
> > A symphony can have a dynamic range that taxes the abilities
> > of fine audiophile equipment to reproduce accurately.
>
> Again, more nonsense. The ambient noise level of the listening
> environment would undoubtly be the limiting factor here. The
> typical audiophile has, if anything, _better_ gear than what was
> used to make the typical recording, not to mention broadcast it.
Equipment with a 90 db dynamic range (the human ear doesn't even have
this capability) is rather useless in even a Rolls going 65 MPH down the
road.
By the way, I would venture a guess that the number of people reading
this newsgroup who have actually heard the true capability of analog AM
stereo could be counted on the fingers of one hand.
ab...@mix.com
> Equipment with a 90 db dynamic range (the human ear doesn't even have
> this capability) is rather useless in even a Rolls going 65 MPH down the
> road.
I like to explain it this way - let's call the threshold of pain 128dB
and then let's say we had a pretty quiet location to listen. Even so
the ambient noise is still going to be around 40~50dB. But even being
generous and calling it 40 only leaves 88dB of dynamic range available
to hear anything at all... if your stuff can actually emit 128dB in the
first place, that is. It probably can not.
For the truly curious Radio Shack sells a sound pressure level meter
that's actually fairly accurate - all this can be seen first-hand for
about 30 US bucks....
Billy Y..
Philip J. Koenig
Very often not true when talking about classical recordings.
Since audiophile listening equipment doesn't broadcast radio
signals, the latter comparison isn't particularly germane.
Philip J. Koenig
It is also a known fact that human beings can "hear into the noise
floor", particularly when discussing analog recording systems. So
things aren't nearly as simple as you would imply. Dynamic range
is also hardly the only challenge in reproducing quality audio.
(but because it's easily quantified into a simplistic number, people
love to quote such numbers as "proof" of this or that)
I'm reminded of the scene from the film (I think) Ruthless People,
where the audio salesman convinces the ignorant buyer that the
product he's pushing is superior because the volume dial goes up to 11..
Steve Pope
> It is also a known fact that human beings can "hear into the noise
> floor", particularly when discussing analog recording systems. So
> things aren't nearly as simple as you would imply. Dynamic range
> is also hardly the only challenge in reproducing quality audio.
A number of musical instruments have > 100 dB dynamic range,
including the piano and many percussion instruments.
Human perception of sound is subjective enough that it's
difficult to argue how much range people can "perceive",
however, we can certainly perceive sounds over this entire
range.
Steve
John Higdon
Steve Pope <spo...@speedymail.org> wrote:
> A number of musical instruments have > 100 dB dynamic range,
> including the piano and many percussion instruments.
Do you have a reference for that? Given the magnitude of a 100 db ratio,
that's a pretty amazing statement. It certainly is not true in the
course of actual musical performance.
> Human perception of sound is subjective enough that it's
> difficult to argue how much range people can "perceive",
> however, we can certainly perceive sounds over this entire
> range.
The human ear can also be fooled in every aspect of audio, including the
perception of dynamic range. Since recordings cannot and do not capture
the essence of live music, obviously they must be enjoyed as
entertainment in their own right.
ab...@mix.com
> > It is also a known fact that human beings can "hear into the noise
> > floor", particularly when discussing analog recording systems.
Well guess what - who the hell wants to listen to anything like that?
Asnwer: Besides you, no one at all.
> > So things aren't nearly as simple as you would imply.
No, a little knowledge is a dangerous thing, and you are an excellent
example of exactly that.
> > Dynamic range is also hardly the only challenge in reproducing
> > quality audio.
But unfortunately dynamic range is what's being discussed here.
> A number of musical instruments have > 100 dB dynamic range,
> including the piano and many percussion instruments.
> Human perception of sound is subjective enough that it's
> difficult to argue how much range people can "perceive",
> however, we can certainly perceive sounds over this entire
> range.
Within some limits - for example if you've just been taken to
the threshold of pain don't expect to be able to immediately
hear a pin drop right after that...
Anyway the whole key to success with all this is the ability
to cram all these dynamics into some electronic medium and
then replicate them well enough so everything can be heard
dispite all the limitations of the recording medium, not to
mention acoustic environment where they will be heard.
This is what the so-called recording 'engineer' (sound mixer)
is supposed to accomplish...........
Billy Y..
ab...@mix.com
> > A number of musical instruments have > 100 dB dynamic range,
> > including the piano and many percussion instruments.
> Do you have a reference for that?
Well, begin with the equal loudness contours, called the Fletcher-Munson
curves, as shown on page 33 (Chpater 2.7) of the "New Audio Cyclpedia"
which is now published by Sams. You can probably find this on the net,
but my trusty VT510 terminal doesn't do graphics, so you have to look..
Therein you'll see it's all frequency dependent, etc.
Since you work in radio, I highly recommend this book. It is extremely
thorough.
> Given the magnitude of a 100 db ratio,
> that's a pretty amazing statement. It certainly is not true in the
> course of actual musical performance.
Correct.
> The human ear can also be fooled in every aspect of audio, including the
> perception of dynamic range. Since recordings cannot and do not capture
> the essence of live music, obviously they must be enjoyed as
> entertainment in their own right.
Only God knows how true this really is!
Billy Y..
John Higdon
> Anyway the whole key to success with all this is the ability
> to cram all these dynamics into some electronic medium and
> then replicate them well enough so everything can be heard
> dispite all the limitations of the recording medium, not to
> mention acoustic environment where they will be heard.
>
> This is what the so-called recording 'engineer' (sound mixer)
> is supposed to accomplish...........
I couldn't agree with you more.
As someone who has recorded live music professionally on everything from
old Ampex custom multitrack gear to present day digital storage systems,
and edited and post-mixed those recordings for broadcast, mass-copy
release, as well as archiving, I can tell you that forty years of
experience in that field is not going to be condensed into two or three
Usenet posts...nor is any attempt going to be made to do so, at least
not by me, and certainly not to people who haven't a clue.
Jeff Liebermann
Perception is everything.
I suppose that I should mention subliminals and their presence in
commercial audio of all sorts. This is where an advertising message,
or background sound "theme" is added for the desired psychological
effect. A good example is the background "noise" added to "The
Exhorcist" movie sound track to create a feeling of irritation and
uneasiness. The "noise" was the sound of angry bees in a shaken jar
delivered at between -30dB and -50dB below peak audio level. You
couldn't really hear it, but it was certainly had an effect. TV game
shows that advertise products sometimes have someone talking under the
applause. (Ever notice how much applause there was on TV game shows?)
There's usually someone chanting "buy the car, it will improve your
sex life" or something similar under the applause. Back in the late
60's, when game shows still used canned applause, our college class
was able to use an HP auto-correlator to differentially cancel the
applause and extract some of the chanting. Lots of other examples.
(Yeah, it's all a conspiracy).
The problem is that the dynamic range of the audio has a significant
impact on the ability to insert subliminals. Dolby A, which
artificially clobbers the low end is fatal. Same with any form of
perceptual compression (MP3, WMA, MP4, DRM, iBiquity). The only thing
that works is having the subliminals added to an existing sound
"carrier" such as background noises, studio "quiet" sounds, applause,
traffic noise, and such. However, in order for this to work, the
dynamic range must be artificially expanded after compression to
accomidate the subliminals. That's a hard sell when most rock music
is compressed to almost square waves (maximum distortion) but the ad
agencies are asking for large dynamic ranges.
Anyway, I hope this explains why there is some insistance on wide
dynamic ranges for content that neither needs (or deserves) it, and
for a population that cannot directly perceive it. Dynamic range is
not all for the audiophile.
--
Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
John Higdon
Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> Anyway, I hope this explains why there is some insistance on wide
> dynamic ranges for content that neither needs (or deserves) it, and
> for a population that cannot directly perceive it. Dynamic range is
> not all for the audiophile.
Nor does even the audiophile always need or even want it. While hearing
a modern (or even legendary legacy) recording on excellent reproduction
equipment in a well-engineered listening room is, at least for me, akin
to a religious experience, the majority of listening is done at a point
much higher on the casual scale. This would include most of what is
broadcast on commercial (or even non-commercial) radio.
The number of listeners using top-drawer equipment in environments and
circumstances where such equipment might even might make a difference
(or even using such equipment at all) is statisitically insignificant.
The technical limitations of the broadcast medium are swamped by actual
use of that technology.
Listening to concert music on KDFC (AM) in the car was always more
satifying to me than vain attempts to make any sense out of a CD played
in the same environment.
Philip J. Koenig
> Steve Pope <spo...@speedymail.org> writes (quoting Philip J. Koenig):
>
> > > It is also a known fact that human beings can "hear into the noise
> > > floor", particularly when discussing analog recording systems.
>
> Well guess what - who the hell wants to listen to anything like that?
>
> Asnwer: Besides you, no one at all.
My statement was not suggesting we're going to all sit around and
listen to tape hiss as a way to pass the time. I was simply pointing
out that simplistic proclamations about what "dynamic range" is are
not particularly thorough in their characterization of what we can
and cannot hear.
> > > So things aren't nearly as simple as you would imply.
>
> No, a little knowledge is a dangerous thing, and you are an excellent
> example of exactly that.
Nice try.
> > > Dynamic range is also hardly the only challenge in reproducing
> > > quality audio.
>
> But unfortunately dynamic range is what's being discussed here.
Actually we were discussing Richard's implication that dynamic range
was the primary determinant of perceived audio quality in radio
broadcasts, and I am pointing out that this is an oversimplification
of what is necessary to create a reasonable facsimile of "hifi" or
impression of live music.
Philip J. Koenig
absolutel...@verislimesucks.com (John Higdon) writes...
I think there is a lot of assumption that the benefit of wide dynamic
range is simply to be able to hear the quiet parts and loud parts
without changing the volume setting.
In reality, systems with a wide dynamic range also typically have a
beneficial impact on "all that stuff in the middle", ie whether
someone hitting a drum sounds like the drum is made out of a muffled
pillow, or a real drum. It's not all about the cannon shots in the
1812 overture, followed by a quiet muffled solo plucking on violin
strings, and whether you have to turn up the volume to hear the latter
or not.
Steve Pope
>Steve Pope <spo...@speedymail.org> writes (quoting Philip J. Koenig):
>> A number of musical instruments have > 100 dB dynamic range,
>> including the piano and many percussion instruments.
>> Human perception of sound is subjective enough that it's
>> difficult to argue how much range people can "perceive",
>> however, we can certainly perceive sounds over this entire
>> range.
>Within some limits - for example if you've just been taken to
>the threshold of pain don't expect to be able to immediately
>hear a pin drop right after that...
That's correct; when subjected to loud sounds, a mechanism
kicks in that reduces the sensitivity of hearing.
John -- no, I don't have a reference to the dynamic range
of instruments, I'm just going from memory. But it
doesn't seem too amazing to me; either a piano or
a percussion instrument can probably create the softest
audible sound (0 dB), or could be about as loud as
a lawnmower (100 dB) if you bank on it hard enough.
Steve
John Higdon
Steve Pope <spo...@speedymail.org> wrote:
> That's correct; when subjected to loud sounds, a mechanism
> kicks in that reduces the sensitivity of hearing.
Including, ultimately in the long term, ear damage.
Philip J. Koenig
writes...
That all depends on distance. A single piano in a concert hall
certainly isn't capable of creating 100db spl at the listener's
ear, unless all the concertgoers are crammed inside its lid.
Amplified musical instruments, on the other hand, are something
else entirely.
The main reason symphonic music has a wider dynamic range than
most other forms of popular (acoustical) music, is the simple
fact that the sheer number of instruments provide for a wider
range for anything from 1 musician/instrument playing, to something
approaching 100 musicians playing at the same time.
Eric Weaver
> Whatever you do, make sure your equipment is powere by the
> proper power cord.
>
> http://www.stereotimes.com/cables071003.shtm
>
> That's a joke page, right? People don't blow six hundred bucks on
> power cords, right?
Jeez, I'm in the wrong business...
John Higdon
Javier Henderson <jav...@KJSL.COM> wrote:
> That's a joke page, right? People don't blow six hundred bucks on
> power cords, right?
Obviously you haven't hob-knobed in the rarified world of audio
crackpottery. On the studio end, you have oxygen-free cable (that can
cost more than the recorders it interconnects) and on the playback end
you have everything from blessed tube-type electronics to concrete
turntables. Even more impressive that the touted audio quality is the
stratopheric cost of the goods.
In this business, you cannot help but run into true believers on a
regular basis.
John Higdon
Eric Weaver <we...@sigma.net> wrote:
It was the late Walt Palmer who introduced me to the broadcast wing of
audio religion. (No doubt you have laid hands on his phono preamps at
one time or another. They were in a number of stations before the vinyl
disc finally disappeared entirely.) He spent years handcrafting the main
audio console for KDFC to be used when the studio moved off the
mountain. In the process of vain attempts to speed up the work (you
don't rush a craftsman), I learn much about the faith.
John Higdon
Javier Henderson <jav...@KJSL.COM> wrote:
> I know I saw these little tripods, hand made of a rare Brazilian
> hardwood, designed to keep the speaker cables off the floor because of
> some little known deleterious effect on the audio signals.
You don't want that oxygen-free wire getting dirty.
ab...@mix.com
> That's a joke page, right? People don't blow six hundred bucks on
> power cords, right?
Somebody must cause these guys have plenty of competition.
I found about a dozen different ones when I was searching
for colored IEC power cords about a week ago....
There are even reviews of them. "No difference with analog
sources but digital was improved" and similar quackery abound.
Some of them do look pretty cool, but not for that kind of
money. Seeing it all was quite a shock..............
Billy Y..
John Higdon
> Javier Henderson <jav...@KJSL.COM> writes:
>
> > That's a joke page, right? People don't blow six hundred bucks on
> > power cords, right?
>
> Somebody must cause these guys have plenty of competition.
> I found about a dozen different ones when I was searching
> for colored IEC power cords about a week ago....
>
> There are even reviews of them. "No difference with analog
> sources but digital was improved" and similar quackery abound.
I have had audio crackpots, people who were otherwise fairly sane, sit
and tell me about using green Sharpie markers around the edge of CDs
improving the audio.
There is no ceiling to the heights of screwball audio rituals and
iconography.
"AM, Brother! AM, Sister!"
Jeff Liebermann
<absolutel...@verislimesucks.com> wrote:
>While hearing
>a modern (or even legendary legacy) recording on excellent reproduction
>equipment in a well-engineered listening room is, at least for me, akin
>to a religious experience, the majority of listening is done at a point
>much higher on the casual scale. This would include most of what is
>broadcast on commercial (or even non-commercial) radio.
Well, I'm a true believer in the law of diminishing returns. For each
increment in performance, you get to spend an exponentially increasing
number of dollars. After a while, the performance doesn't increment,
but the dollars keep climbing. Let's just say I practice the art of
economical acoustics.
>The number of listeners using top-drawer equipment in environments and
>circumstances where such equipment might even might make a difference
>(or even using such equipment at all) is statisitically insignificant.
>The technical limitations of the broadcast medium are swamped by actual
>use of that technology.
I'm not so sure. Once upon a time, I sold hi-fi's for Federated
Purchaser in Smog Angeles. My guess(tm) is that for every 100
conventional systems sold, there would be one lunatic who would empty
the bank account on his idea of the ultimate hi-fi. He would spend
about 100 times as much as necessary (including the dealer install).
Money does strange things to people. Anyway since my commission was
based upon an increasing percentage of the total selling price, I
tended to concentrate on the big spenders. Many had tin ears and were
only interested in impressing their friends and accomplices. One
memorable buyer insisted that the mark of quality was the ability of
the music system to fracture a thin wine glass. I delivered but wore
ear muffs during the test. Later, I made some side profit selling
audio test equipment to my former fanatical customers as they often
found it necessary to prove that they had the best hi-fi on the
planet. I also built an "ambience and presence" meter, but didn't
have the guts to sell it to anyone. For some, no amount of "fi" is
sufficient.
>Listening to concert music on KDFC (AM) in the car was always more
>satifying to me than vain attempts to make any sense out of a CD played
>in the same environment.
My diesel pickup only has an AM radio. If I can hear what little
music belches forth over the VHF FM, scanner, engine noise, and road
noise, I consider it sufficient.
Once upon a time, I helped orchestrate a psychology experiment
involving perception. This was about 1968 so the technology was
little better than crude. We build a studio board using 10 turn
helipots for all the controls. As I vaguely recall, there were 12
tracking stereo controls covering everything from bass boost, treble,
gain, delay, reverb (spring delay line), reverb delay, compression,
expansion, and such. We would play a recording of the skool orchestra
playing a variety of tunes. Some included some singers. The
recordings were made were made with ribbon (condenser) mics. The
auditorium walls were plastered with gym mattresses and curtains to
deaden the reflections. I ran the board and did the equalization of
the mics to get the recording as close to flat as possible. This was
the starting point of the test.
Each victim was asked to adjust the knobs so that the music sounded
best. There was little relation to the knob position and the effects.
Some controls were (accidentally) installed backwards. The victim
could not see the numbers (position) of the controls. The initial
positions were a flat level with zero reverb.
We ran about 20 people through this test over a period of about 2
weeks. We found some interesting commonality. Initially, almost
everyone would add about 20dB bass and 10dB treble boost with fairly
heavy reverb leaving a big hole in the middle. This made it sound
like the inside of a sheet metal train station. The controls would
stay there for about 30 minutes. However, after 30 minutes of getting
hammered by this abomination, the bass and treble boost would drift
downward, and the reverb intensity would return to something vaguely
resembling a real auditorium. One victim, that was willing to do this
for 8 hrs (with minimum breaks), eventually ended up with almost
totally flat and no reverb.
Three classes, totaling about 150 students wrote 150 different
conclusions from the experiment. My version was that un-natural
sounds attract attention, sound really "good" for a while, and are
seriously fatiguing. If you're playing short cuts, interspersed with
commercials and drivel, then most people will boost the lows and
highs, crank up the reverb, compress the output, and basically create
an un-natural sounding mess. However, if you're playing background
music, full CD's, or streaming music, something closer to flat is
preferable.
As always, perception is everything.
John Higdon
Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> I'm not so sure. Once upon a time, I sold hi-fi's for Federated
> Purchaser in Smog Angeles. My guess(tm) is that for every 100
> conventional systems sold, there would be one lunatic who would empty
> the bank account on his idea of the ultimate hi-fi. He would spend
> about 100 times as much as necessary (including the dealer install).
> Money does strange things to people. Anyway since my commission was
> based upon an increasing percentage of the total selling price, I
> tended to concentrate on the big spenders. Many had tin ears and were
> only interested in impressing their friends and accomplices. One
> memorable buyer insisted that the mark of quality was the ability of
> the music system to fracture a thin wine glass. I delivered but wore
> ear muffs during the test. Later, I made some side profit selling
> audio test equipment to my former fanatical customers as they often
> found it necessary to prove that they had the best hi-fi on the
> planet. I also built an "ambience and presence" meter, but didn't
> have the guts to sell it to anyone. For some, no amount of "fi" is
> sufficient.
I have a friend in this biz who has been making extra money on the side
building tube-type amplifiers of his own design and selling them to
crackpot audiophiles. The design is laughable (his own words) and the
componentry bizarre (again, his own description), but he has a dedicated
clientelle who wouldn't dream of using anything else. These people have
decided that these retro-technology power amps cannot be beat and they
shell out big time to buy these trinkets, crafted from my friend's
garage floor sweepings.
> The
> recordings were made were made with ribbon (condenser) mics.
Ribbon (variable reluctance, velocity-activiated magnetic transducers)
or condenser (variable capacitance, pressure-activated transducers)?
> We ran about 20 people through this test over a period of about 2
> weeks. We found some interesting commonality. Initially, almost
> everyone would add about 20dB bass and 10dB treble boost with fairly
> heavy reverb leaving a big hole in the middle. This made it sound
> like the inside of a sheet metal train station. The controls would
> stay there for about 30 minutes. However, after 30 minutes of getting
> hammered by this abomination, the bass and treble boost would drift
> downward, and the reverb intensity would return to something vaguely
> resembling a real auditorium. One victim, that was willing to do this
> for 8 hrs (with minimum breaks), eventually ended up with almost
> totally flat and no reverb.
Radio station program directors used to follow the first half of this
and demand that the station's curve look like a bowl. It took years for
them to figure out that this led to listener fatigue, as indicated by
high cumes and low quarter hours. Most stations are now fairly flat.
> Three classes, totaling about 150 students wrote 150 different
> conclusions from the experiment. My version was that un-natural
> sounds attract attention, sound really "good" for a while, and are
> seriously fatiguing. If you're playing short cuts, interspersed with
> commercials and drivel, then most people will boost the lows and
> highs, crank up the reverb, compress the output, and basically create
> an un-natural sounding mess. However, if you're playing background
> music, full CD's, or streaming music, something closer to flat is
> preferable.
>
> As always, perception is everything.
The founder of Orban Associates, the leading audio processing and
modulation control equipment supplier to the broadcast industry, has
always insisted that what he is selling to broadcasters is perception.
Jeff Liebermann
<absolutel...@verislimesucks.com> wrote:
>I have a friend in this biz who has been making extra money on the side
>building tube-type amplifiers of his own design and selling them to
>crackpot audiophiles.
He would do well to expand into ham radio, where "radios that glow in
the dark" have a following. Incidentally, I got my start in
electronics as a kid reading Popular Electronics. What got my
attention was someone named Charles Torelli and his "Turn your house
wiring into a giant 500 ft TV antenna". I understood whey it wouldn't
work, but was fascinated by the fact that every issue had huge
advertisements and testimonials. Even when New York state indicted
him for fraud, the ads continued.
>> The
>> recordings were made were made with ribbon (condenser) mics.
>Ribbon (variable reluctance, velocity-activiated magnetic transducers)
>or condenser (variable capacitance, pressure-activated transducers)?
Sorry, my screwup. Condenser. Predecessor to the currently
fashionable electret microphones. Very expensive microphones bummed
from some recording studio. They had the flattest response available,
with very little added noise from the preamps. I don't recall the
exact model.
>Radio station program directors used to follow the first half of this
>and demand that the station's curve look like a bowl. It took years for
>them to figure out that this led to listener fatigue, as indicated by
>high cumes and low quarter hours. Most stations are now fairly flat.
As I vaguely recall from the 1960's, some effort was put into tweaking
the frequency response to the whims of whomever was in control. The
AM stations would adjust their response so that the common 5 tube ACDC
receiver would sound reasonable. There was a big hole below about
100Hz to get rid of hum and speaker resonances plus a boost at the
high end 2.5-3KHz to compensate for lousy demodulator and speaker
response. However, that's when AM stations still played music. With
talk, it was two slight peaks at 700Hz and 1700Hz to conform to the
power distribution of the human voice. I don't recall what tweaking
was done at FM stations. At three college FM stations, we chopped off
the low end at about 30Hz to get rid of turntable rumble. Other than
that, it was as flat as possible. Well, actually we did chop off the
highs from the tape automation at about 8KHz to get rid of the tape
hiss.
>The founder of Orban Associates, the leading audio processing and
>modulation control equipment supplier to the broadcast industry, has
>always insisted that what he is selling to broadcasters is perception.
Sell the sizzle, not the steak. Yeah, you can sell perception. "It's
the feeling, not the music?" However, it's rather tough to measure
perception. That's what my ambience and presence (fake) meter was
alleged to do; quantify intangibles. What I've seen when someone
sells intangibles, is a tendency toward hype. Orban may understand
the limitations and compromises involved in perceptual compression,
but the average consumer does not. Hell, I have problems
understanding some of the subtleties of MP3 and MP4 compression. Joe
Sixpack gets told that his flashy new AM stereo multimedia iBiquity
receiver is "CD quality stereo", and he believes it. The telco
version is "you can hear a pin drop", which I've tried and you cannot.
Short of educating Joe Sixpack, I don't see a solution. As long as
Orban doesn't degenerate into selling hype, you won't hear me
complaining.
Incidentally, I still can't find an iBiquity software decoder for a
PC. Duz such a thing exist (as there is for DRM/DREAM)?
http://drm.sourceforge.net
--
Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
John Higdon
Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> At three college FM stations, we chopped off
> the low end at about 30Hz to get rid of turntable rumble. Other than
> that, it was as flat as possible.
Low-end cutoff is still employed at many stations to keep audio products
from interfering with AFC loops in STLs or exciters. This wobbling of
the baseband is one of the primary causes of modulation overshoots,
right after LPF overshoots...which Orban solved in the seventies.
> Well, actually we did chop off the
> highs from the tape automation at about 8KHz to get rid of the tape
> hiss.
That's a pretty effective means of noise reduction, especially
considering the negligible amount of programming that really exists on
those tapes above the cutoff frequency.
> Orban may understand
> the limitations and compromises involved in perceptual compression,
> but the average consumer does not.
Of course, that understanding is Bob's stock in trade. Over dinner one
time, he went on at length about the limitations digital processing
would have recreating all of his ear-fooling techniques. That was before
DSP had hardware with real horsepower available, but it gave me insight
as to the real science at play.
> Hell, I have problems
> understanding some of the subtleties of MP3 and MP4 compression.
Don't feel bad. This is not simple stuff. Greg over at Orban has tried
repeatedly to explain some of that technology and it goes right over my
head. The encoder/decoder chain is literally a software machine that
does more to the audio than I care to think about. There is band
splitting, controlled interaction (and independence) between bands,
compression and expansion of bands on a dynamically-analyzed basis,
etc., etc.
> Joe
> Sixpack gets told that his flashy new AM stereo multimedia iBiquity
> receiver is "CD quality stereo", and he believes it.
The term "CD quality" has, in my opinion, become code for "not
CD-quality". CD quality is that which comes off a standard Philips
Compact Disc. Everything else is some degree of squash. The only
question is "how much"? I now have music on everything from CDs down to
old-codec low-bitrate MP3s and my arms haven't fallen off yet.
It is now amusing to think back to when we were told that DAT would be
superior to CDs because of the higher sample rate. As if the difference
between uncompressed 44.1KHz and 48KHz would be some sort of quality
shocker, especially considering what's out there now!
> As long as
> Orban doesn't degenerate into selling hype, you won't hear me
> complaining.
Bob does sell hype...to station programmers. Fortunately, he still has
to sell the engineers, and that means there still has to be some
mechanism behind the razzle-dazzle.
On a side note, I have found that calling IBOC out on its sartorial
splendor is an instant way to raise Bob's blood pressure. I think IBOC
is marketing hype and a waste of time when it comes to audio quality
improvement. Bob disagrees...vehemently. But I can understand that
"digital broadcasting" means a whole new market out there for equipment
vendors.
> Incidentally, I still can't find an iBiquity software decoder for a
> PC. Duz such a thing exist (as there is for DRM/DREAM)?
It might be too new. It was changed from the original to AAC+ not that
many moons ago. Real One has a beta player that will decode AAC+, but
I'm not sure if the broadcast/web-stream versions are interoperable.
I'll check with Greg.
ka...@rahul.net
wrote:
>Yep. That was my reaction as well.
>
>I know I saw these little tripods, hand made of a rare Brazilian
>hardwood, designed to keep the speaker cables off the floor because of
>some little known deleterious effect on the audio signals.
>
>-jav
I'd be mpore concerned about the deleterious effect on my
wallet. It has to be cheaper just not to ride your motorcycle around
in the living room.
ka...@rahul.net
<See_email_@ddress_below.This_one_is.invalid> wrote:
>That all depends on distance. A single piano in a concert hall
>certainly isn't capable of creating 100db spl at the listener's
>ear, unless all the concertgoers are crammed inside its lid.
Well I'm sure all those (in another fiber of this thread)
who'd pay $600 for a power cord wouldn't mind hopping into the piano
if it would enhance the experience. :-)
ka...@rahul.net
<je...@comix.santa-cruz.ca.us> wrote:
> ... One
>memorable buyer insisted that the mark of quality was the ability of
>the music system to fracture a thin wine glass.
Obviously there's money to be made in custom glassmaking for
people like this.
John Higdon
ka...@rahul.net wrote:
And in the construction and sale of soundproof cases to keep the wine
glass stock.
ka...@rahul.net
<absolutel...@verislimesucks.com> wrote:
>In article <7us4301n659ivvri1...@4ax.com>,
> ka...@rahul.net wrote:
>
>> On Tue, 17 Feb 2004 07:33:13 GMT, Jeff Liebermann
>> <je...@comix.santa-cruz.ca.us> wrote:
>>
>> > ... One
>> >memorable buyer insisted that the mark of quality was the ability of
>> >the music system to fracture a thin wine glass.
>>
>>
>> Obviously there's money to be made in custom glassmaking for
>> people like this.
>
>And in the construction and sale of soundproof cases to keep the wine
>glass stock.
I just finished reading the article on power corde. I'm still
not convinced they didn't steal it from TheOnion.com. I believe Herb
Caen used to call this stuff "the 'prismatic luminescence' school of
wine writing.
I do have to wonder what difference you can expect to make in
the last six feet with electricity which has been through stepdown
transformers a few times from 100KV or so, then traveled through your
house wiring with fluorescents, dimmers, computers, etc on the same
line. Not to mention conversion to DC with accompanying filtering.
I am again reminded of the cartoon where a math prof has a
blackboard full of equations with a set of parens in the middle,
containing the words (at this point a miracle happens).
John Higdon
ka...@rahul.net wrote:
> I do have to wonder what difference you can expect to make in
> the last six feet with electricity which has been through stepdown
> transformers a few times from 100KV or so, then traveled through your
> house wiring with fluorescents, dimmers, computers, etc on the same
> line. Not to mention conversion to DC with accompanying filtering.
That's according to YOUR science. Audio crackpots transcend such
limitations.
Fred Viles
4ax.com:
>...
> I am again reminded of the cartoon where a math prof has a
> blackboard full of equations with a set of parens in the middle,
> containing the words (at this point a miracle happens).
LOL! I had that cartoon on one of my favorite T-shirts (RIP). There
were two profs looking at the board and one is saying to the other "I
think you need to be a bit more explicit in step 3."
Thanks for reminding me...
- Fred
Jeff Liebermann
<absolutel...@verislimesucks.com> wrote:
>Low-end cutoff is still employed at many stations to keep audio products
>from interfering with AFC loops in STLs or exciters. This wobbling of
>the baseband is one of the primary causes of modulation overshoots,
>right after LPF overshoots...which Orban solved in the seventies.
I missed all that. None of the stations I was involved with had
remote studios or STL radios. We used heavily modified VHF FM
(wideband) radios for remote pickups at sports events. Good enough
for voice.
>> Hell, I have problems
>> understanding some of the subtleties of MP3 and MP4 compression.
>Don't feel bad. This is not simple stuff. Greg over at Orban has tried
>repeatedly to explain some of that technology and it goes right over my
>head.
Any sufficiently advanced technology is indistinguishable from magic.
After reading some articles on perceptual compression technology, I
tend to suspect it really is magic.
>The encoder/decoder chain is literally a software machine that
>does more to the audio than I care to think about. There is band
>splitting, controlled interaction (and independence) between bands,
>compression and expansion of bands on a dynamically-analyzed basis,
>etc., etc.
More magic. One of my less entertaining ideas was to setup a
streaming audio server at my palatial office and belch recycled audio
from the local ham radio repeater. That's when I discovered that much
of the magic in compression takes lots of time. The system delay was
anywhere between 1 second and 2 minutes. Delay is not an issue when
belching streaming music or pre-recorded content, but is pure hell if
you're trying to use the audio stream in real time. Shoutcast with
Winamp 2 was the worst at 2 minutes. Speak Freely was the fastest but
was limited to speech. I finally settled on Windoze Media Encoder 7
at about 2 seconds. Windoze Media Encoder 9 was even longer.
Anything I don't understand, must obviously be magic.
>The term "CD quality" has, in my opinion, become code for "not
>CD-quality". CD quality is that which comes off a standard Philips
>Compact Disc.
Once upon a time (about 1979), I worked for Intech Inc in Santa Clara.
One of the other divisions was working on a secret project for Sony.
It turned out to be the A/D and D/A sub-system of the original cdrom.
Lots of discussions about fidelity, noise, and technical limits. Two
system were tested, 14bit and 16bit. The 16bit cost twice as much as
the 14bit. There was a substantial difference in quantization noise.
However, they discovered that the only way to get rid of the motor
noise was to drop 2bits (LSB) out of 14bits, 14 bits was the immediate
winner. In other words, if Sony had wanted a more fidelity, they
would have had to reduce the motor noise about 4 times, and double the
price of the electronics.
Incidentally, the infamous cdrom "red book" standard was a bright red
Intech ring binder that someone at either Sony or Philips "borrowed"
from Intech.
>It is now amusing to think back to when we were told that DAT would be
>superior to CDs because of the higher sample rate. As if the difference
>between uncompressed 44.1KHz and 48KHz would be some sort of quality
>shocker, especially considering what's out there now!
Well, it certainly was an improvement over Philips cassette tapes, 4
track, 8 track, and 1/4" reel to reel. I thought that DAT had quite a
bit of promise. However, that attorneys for various intellectual
property owners failed to appreciate the benifits of accurate
reproduction, and did a fairly good job of preventing consumer DAT
products from ever entering the US at a reasonable price. The same
was also done with Mini-Disk recorders, which I'm told are all over
Europe, but are barely noticed in the US. Yeah, it's a conspiracy.
>Bob does sell hype...to station programmers. Fortunately, he still has
>to sell the engineers, and that means there still has to be some
>mechanism behind the razzle-dazzle.
Ask him how iBiquity handles subliminal inserts without distorting or
deleting the content. Figure on -30dB below peak audio.
>On a side note, I have found that calling IBOC out on its sartorial
>splendor is an instant way to raise Bob's blood pressure. I think IBOC
>is marketing hype and a waste of time when it comes to audio quality
>improvement. Bob disagrees...vehemently. But I can understand that
>"digital broadcasting" means a whole new market out there for equipment
>vendors.
IBOC wouldn't even exist were it not for the threat presented by
Satellite broadcasters Sirius and XM. What almost everyone seems to
be ignoring is that most people buy satellite audio receivers to get
away from the commericals, announcers, promos, PSA's, and general
butchery of the music. I don't expect it to last, but it is the
ultimate selling point. National coverage is nice for the truckers,
but Joe Sixpack doesn't travel farther than the local pub. I suspect
that the digital broadcasters will ignore all this, continue to
dispense the same old content, and wonder why everyone didn't throw
away their satellite audio receivers.
>> Incidentally, I still can't find an iBiquity software decoder for a
>> PC. Duz such a thing exist (as there is for DRM/DREAM)?
>It might be too new. It was changed from the original to AAC+ not that
>many moons ago. Real One has a beta player that will decode AAC+, but
>I'm not sure if the broadcast/web-stream versions are interoperable.
>I'll check with Greg.
Duh. I didn't think of checking the MP4 player vendors. Looks like
Apple Quicktime 6 and iTunes 4 will do it.
http://www.apple.com/mpeg4/aac/
Reading between the lines, there appears to be some convegence between
the DRM (digital radio mondiale) and the other AAC decoders. They're
all simply methods of delivering an MP4 data stream. I'll try the DRM
decoder and Quicktime on the SF iBiquity stations and see what breaks.
Thanks much.
ka...@rahul.net
And thanks for reminding me of the second prof. If it wasn't
in Far Side, it should have been.
Philip J. Koenig
writes...
>
> I know I saw these little tripods, hand made of a rare Brazilian
> hardwood, designed to keep the speaker cables off the floor because of
> some little known deleterious effect on the audio signals.
>
> -jav
Without even looking at the page referenced in the link, I can tell
you that there are many audiophile types that swear by that kind of
thing.
Personally I'm somewhat skeptical, but I try to keep an open mind.
Those who refuse to learn from history can often look pretty dumb
later on when they make sweeping proclamations about something that
seems reasonable at the time based on current knowledge, but which
may turn out to be completely wrong later after new things are
discovered.
When Edison's wax cylinder was first invented or marketed, many
proclaimed it made a "perfect reproduction" of sound. Likewise
the CD, etc. Obviously later on we discovered a plethora of ways
to scientifically quantify the failings of these various sound
reproduction technologies, yet people persist in their grand
proclamations that "it can't get any better because our current
measuring instruments can't detect it".
The bottom line is, the human ear is the ultimate benchmark, and
some day I guarantee you that we will find ways to quantify subtle
aspects of sound reproduction that as of 2004 we were all convinced
(based on "conventional wisdom") were "nonexistent" and therefore
"unimportant" factors. The same concepts apply to most scientific
endeavors. (see .sig)
Philip J. Koenig
absolutel...@verislimesucks.com (John Higdon) writes...
> In article <c0s00n$958$1...@reader1.panix.com>, ab...@MIX.COM wrote:
>
> > Javier Henderson <jav...@KJSL.COM> writes:
> >
> > > That's a joke page, right? People don't blow six hundred bucks on
> > > power cords, right?
> >
> > Somebody must cause these guys have plenty of competition.
> > I found about a dozen different ones when I was searching
> > for colored IEC power cords about a week ago....
> >
> > There are even reviews of them. "No difference with analog
> > sources but digital was improved" and similar quackery abound.
>
> I have had audio crackpots, people who were otherwise fairly sane, sit
> and tell me about using green Sharpie markers around the edge of CDs
> improving the audio.
>
> There is no ceiling to the heights of screwball audio rituals and
> iconography.
>
> "AM, Brother! AM, Sister!"
There are actually very sound technical reasons for why the
"green marker" trick does what it does, and if I am not
mistaken it has been scientifically measured and corroborated.
Just because you don't understand it, or because you have a
very strong motivation to disbelieve based on cursory logic,
doesn't mean it is invalid.
John Higdon
Jeff Liebermann <je...@comix.santa-cruz.ca.us> wrote:
> Well, it certainly was an improvement over Philips cassette tapes, 4
> track, 8 track, and 1/4" reel to reel. I thought that DAT had quite a
> bit of promise. However, that attorneys for various intellectual
> property owners failed to appreciate the benifits of accurate
> reproduction, and did a fairly good job of preventing consumer DAT
> products from ever entering the US at a reasonable price. The same
> was also done with Mini-Disk recorders, which I'm told are all over
> Europe, but are barely noticed in the US. Yeah, it's a conspiracy.
I always figured that was a testament to the poor taste of the American
public. I never used analog cassettes, and hated the fact that radio
stations even stooped to using them for giving spot samples to clients,
or for news gathering. They were noisy, had no headroom (hence no real
dynamic range), and worst of all, had outrageous amounts of flutter.
Americans embraced them in portable players, cars, boom boxes, etc.,
etc. This told me volumes about the quality of American listeners' ears.
> IBOC wouldn't even exist were it not for the threat presented by
> Satellite broadcasters Sirius and XM. What almost everyone seems to
> be ignoring is that most people buy satellite audio receivers to get
> away from the commericals, announcers, promos, PSA's, and general
> butchery of the music. I don't expect it to last, but it is the
> ultimate selling point. National coverage is nice for the truckers,
> but Joe Sixpack doesn't travel farther than the local pub. I suspect
> that the digital broadcasters will ignore all this, continue to
> dispense the same old content, and wonder why everyone didn't throw
> away their satellite audio receivers.
Bingo...and it folds right in with what I said above. Broadcasters are
convinced that their salvation is contained in the word "digital". As a
group, broadcasters have always resisted the notion that listener
disappearance is EVER caused by programming issues. Even Bob, whose
fortunes are inexorably linked to the sale of audio processing
equipment, maintains that the success of radio stations lies in the
three "P"s: Programming, programming, and last but not least,
programming.
Engineers are acutely sensitive to this phenomenon. We watch the
station's ratings climb, and the programming and sales departments treat
themselves to trips to Maui in celebration of their brilliance and
success. We watch the ratings drop, and have to endure excoriation from
those same people as they (naturally) assume that there "must be
something wrong with the signal". It is totally predictable, and it
would be funny and amusing if it weren't so annoying.
> >It might be too new. It was changed from the original to AAC+ not that
> >many moons ago. Real One has a beta player that will decode AAC+, but
> >I'm not sure if the broadcast/web-stream versions are interoperable.
> >I'll check with Greg.
>
> Duh. I didn't think of checking the MP4 player vendors. Looks like
> Apple Quicktime 6 and iTunes 4 will do it.
I talked to Greg last night and his take on it is that if done at all,
the receiver manufacturers would, as is done with XM, implement a PC
"solution" in hardware. While the streams (web vs IBOC) are related,
they are not identical and a web decoder will most likely NOT decode an
IBOC stream, which is intended to be used in a closed hardware
environment.
> Reading between the lines, there appears to be some convegence between
> the DRM (digital radio mondiale) and the other AAC decoders. They're
> all simply methods of delivering an MP4 data stream. I'll try the DRM
> decoder and Quicktime on the SF iBiquity stations and see what breaks.
I, for one, would be interested to learn how that comes out.
Eric C. Weaver
> On Wed, 18 Feb 2004 04:02:27 GMT, Fred Viles
> <fv+a...@nospam.usen.epitools.com> wrote:
>
>
>>ka...@rahul.net wrote in news:meg5305bq14uil5hnefdebn9dp3vvmb81b@
>>4ax.com:
>>
>>
>>>...
>>> I am again reminded of the cartoon where a math prof has a
>>>blackboard full of equations with a set of parens in the middle,
>>>containing the words (at this point a miracle happens).
This was almost certainly Sydney Harris, who did a lot of science cartoons. I
remember seeing the one mentioned here and it was in his style.
Here's a link to one of his collections at Amazon:
http://www.amazon.com/exec/obidos/tg/detail/-/0913232424/102-0290988-7193750?v=glance
--
"Without music to decorate it, time is just a bunch of boring
production deadlines or dates by which bills must be paid." --FZ
John Higdon
Javier Henderson <jav...@KJSL.COM> wrote:
> OK. Help us understand it by posting a relevant URL please.
>
> Also, pointers on how a $600 power cord "sounds" better than a $3.95
> one would be most welcome.
The Green Marker Myth was debunked in our own shop. It not only made no
difference in measurable audio specs or bit error rate, double-blind
listening tests never rose above random guess when it came to perceived
improvement. We could deteriorate playback by scribbling all over the
face of the CD (causing significant data errors), but that was about it.
As with other "CD improvers", since there is no scientific basis and no
repeatable results, it is just nonsense hooey with the most notable
effect being the separation of true believers from their money (in this
case for the over-priced magic green markers).
As far as URLs go, I wouldn't be surprised to discover a handful of
sites maintained by True Believers who will insist that Magic Green
Markers, CD Rings, and other magic CD improvers are the savior of the
medium. Of course, anyone who can't hear the difference MUST be a
musical Philistine.
As someone who works with digitized audio every single day of the year,
and who also views a CD for what it is: a digital storage medium, I
can't help but laugh at these fads exploiting the ignorance of early
adopters, adding a voodoo atomosphere to what is now a commonplace
technology. Data is either bit perfect or it is not. Even a Magic Green
Marker can't improve on "perfect". Nor can any of the other quackery.
This all begs the question: if there was any basis to any of the CD
improvement devices, where are they now? Think the public may have grown
up? Could be!
As someone who uses power generated by a full-time UPS (it isn't even
"pure" street power), I'll leave the issue of $600 power cords to others.
John Higdon
Javier Henderson <jav...@KJSL.COM> wrote:
> But look, the head can either read the bits, or it can't. The errors
> can be recovered, or they can't. At that stage, it's digital, and you
> end up with a bitstream or you don't.
One of the popular theories (that I recall from the time those things
were popular) was that the rings, markers, etc., cut down on the work
the servos had to do to keep the beam on track. This in turn put less
erratic load on the power supply, which in turn caused the D/A and audio
circuitry to perform better.
I suppose that it might be possible to design a player badly enough
where such a scenario might pan out, but in the real world, it is snake
oil.
> But hey, if someone can make money selling a CD enhancing marker, more
> power to him.
I've always had a certain respect (and destain) for anyone who can make
a buck off someone else's stupidity. There is certainly a great pool to
draw from! Just read Usenet.
> And if you will excuse me, I have to go and cryogenically treat the
> electrical wiring in my house, so as to not degrade the sinusoidal
> wave that PG&E provides. I hear that phase shifting of just hundredths
> of radians have a perceptible effect on the sound presence.
Take a good look at what rides in on the power waveform and you will go
screaming out into the street. Or...you might be able to think of some
expensive gadgetry you can sell to the masses!
Horrors!
jjn...@sonic.net
The CD green marker actually started on the old usenet group rec.audio as a
joke, and the 'high-end' (which generally doesn't know the difference
between 'red' and 'infra-red') took off with it to produce another one of
their myths, and hence the selling of yet another accessory.
John R Pierce
>Also, pointers on how a $600 power cord "sounds" better than a $3.95
>one would be most welcome.
Heck, I'll settle for an explanation with some actual basis in fact on how
a $200 3' long line level RCA jack interconnect cable between your preamp
and power amp is better than your basic $10 studio grade cable...
John R Pierce
<absolutel...@verislimesucks.com> wrote:
>
>Take a good look at what rides in on the power waveform and you will go
>screaming out into the street. Or...you might be able to think of some
>expensive gadgetry you can sell to the masses!
say, whatever happened to Sola ferroresonant transformers? I went looking
for one a year or so back and couldn't find one anywhere.
Eric Weaver
Maybe if it had Jensen transformers at both ends and was balanced in between
with no signal running on the shield. But I doubt the ones in question are
like that.
Jeez, for a 3-foot interconnect. Mono-crystal silver?
Steve Fenwick
<absolutely.no.spam-D...@equine.announcetech.com>,
John Higdon <absolutel...@verislimesucks.com> wrote:
> In article <c0s00n$958$1...@reader1.panix.com>, ab...@MIX.COM wrote:
>
> > Javier Henderson <jav...@KJSL.COM> writes:
> >
> > > That's a joke page, right? People don't blow six hundred bucks on
> > > power cords, right?
Nah, Real Audiophiles (tm) blow $3k on power cords. Look up "NBS Omega"
sometime.
> > Somebody must cause these guys have plenty of competition.
> > I found about a dozen different ones when I was searching
> > for colored IEC power cords about a week ago....
> >
> > There are even reviews of them. "No difference with analog
> > sources but digital was improved" and similar quackery abound.
>
> I have had audio crackpots, people who were otherwise fairly sane, sit
> and tell me about using green Sharpie markers around the edge of CDs
> improving the audio.
Ah, yes, green markers. I remember those.
> There is no ceiling to the heights of screwball audio rituals and
> iconography.
>
> "AM, Brother! AM, Sister!"
Here's an entertaining site: www.tweakaudio.com. One of the more
interesting tweaks:
"Get rid of all LEDs. LEDs add grain and distortion. Tons of it!!! LCD
displays on CD/DVD players, etc don't distort the sound. If you need
to have an LED for some reason then put a switch on it so it can be
turned off when you are playing music."
I have no idea where to start with this one.
Steve
P.S. I am not a True Audiophile(tm). I stopped drinking the lime
Kool-Aid many years ago.
--
steve <at> w0x0f <dot> com