25 Aug
2008
25 Aug
'08
5:45 a.m.
Hi,
After the latest Intel announcment that they are indeed working
seriously on wireless electricity uses resonance to transmit hte energy
sources I am wondering if anyone has ideas on whether that would affect
audio quality as resonance is an important part of the ambience of live
sound.
Cheers.
--
Patrick Shirkey
Boost Hardware Ltd
25 Aug
25 Aug
6:24 a.m.
Patrick Shirkey wrote:
After the latest Intel announcment that they are
indeed working
seriously on wireless electricity uses resonance to transmit hte energy
sources I am wondering if anyone has ideas on whether that would affect
audio quality as resonance is an important part of the ambience of live
sound.
Wireless energy transfer:
http://en.wikipedia.org/wiki/Wireless_energy_transfer
is acheived using electromagnetic resonant induction.
The resonance of live sound is acoustic resonance:
http://en.wikipedia.org/wiki/Acoustic_resonance
Since these two forms of resonance use different mechanisms
(electromagnetic waves vs sound waves in air) they do not cross
couple, hence there is zero chance for interference between them.
The possibility of interference in electrical/computer audio
equipment (which use electromagnetics) and the wireless electricity
transfer (which also uses electomagnetic waves) deserves far more
concern.
Erik
--
-----------------------------------------------------------------
Erik de Castro Lopo
-----------------------------------------------------------------
"Computer science education cannot make anybody an expert programmer any more
than studying brushes and pigment can make somebody an expert painter."
-- Eric Raymond
6:58 a.m.
Reading "concerns about audio quality" and "intel" in one mail sure
raised
some interest here. Selling worse audio quality as the new high-definition is
probably one of their biggest successes.
Am Montag, 25. August 2008 schrieb Erik de Castro Lopo:
Patrick Shirkey wrote:
Well, there _could_ be some interference as the air around you contains some
water (called humidity). It could be possible that the electromagnetic waves
(a) heat up the water making the room you are in warmer (same principle as
the microwave) or (b) the water molecules move as they are electrical
dipoles. And moving molecules in the gas-phase are exactly what
sound/acoustic is...
But that is only a _very fast_ assumption without looking at the
aforementioned technology of intel.
After the latest Intel announcment that they are
indeed working
seriously on wireless electricity uses resonance to transmit hte energy
sources I am wondering if anyone has ideas on whether that would affect
audio quality as resonance is an important part of the ambience of live
sound.
Wireless energy transfer:
http://en.wikipedia.org/wiki/Wireless_energy_transfer
is acheived using electromagnetic resonant induction.
The resonance of live sound is acoustic resonance:
http://en.wikipedia.org/wiki/Acoustic_resonance
Since these two forms of resonance use different mechanisms
(electromagnetic waves vs sound waves in air) they do not cross
couple, hence there is zero chance for interference between them. The possibility of interference in electrical/computer
audio
equipment (which use electromagnetics) and the wireless electricity
transfer (which also uses electomagnetic waves) deserves far more
concern.
True! And don't forget the fact that others might pick up your energy and use
it without paying.
Arnold
--
visit http://www.arnoldarts.de/
---
Hi, I am a .signature virus. Please copy me into your ~/.signature and send me
to all your contacts.
After a month or so log in as root and do a "rm -rf /". Or ask your
administrator to do so...
7:03 a.m.
Arnold Krille wrote:
Well, there _could_ be some interference as the air
around you contains some
water (called humidity). It could be possible that the electromagnetic waves
(a) heat up the water making the room you are in warmer (same principle as
the microwave)
If this were the case, there would be far greater concerns on the basis
of human health. Humans are roughly 90% water and if this electricity
transfer could heat up water molecules in the air, they are likely to
cause all sorts of adverse health effects in any human that might be in
the vicinity.
Erik
--
-----------------------------------------------------------------
Erik de Castro Lopo
-----------------------------------------------------------------
"Every time you get a windows programmer asking you to write some
ass-backward workaround, think of it as a crack junkie asking you
to help stuff his pipe because his hands are too shaky."
-- Conrad Parker
7:11 a.m.
On Mon, 2008-08-25 at 19:03 +1000, Erik de Castro Lopo wrote:
Arnold Krille wrote:
The MIT scientist who developed the prototype said there is no harm to
humans from the electrical resonance. I believe it works by resonating
at the exact frequency of the metal used to send receive the electrical
charge and that is how the power can be passed between points.
I still have a feeling it will subtly influence the audio quality of a
room.
I have doubt about the effect it will have on electrical equipment due
to static RF as we are not dealing with rf signals in this case.
cheers.
--
Patrick Shirkey
Boost Hardware Ltd
Well, there _could_ be some interference as the
air around you contains some
water (called humidity). It could be possible that the electromagnetic waves
(a) heat up the water making the room you are in warmer (same principle as
the microwave)
If this were the case, there would be far greater concerns on the basis
of human health. Humans are roughly 90% water and if this electricity
transfer could heat up water molecules in the air, they are likely to
cause all sorts of adverse health effects in any human that might be in
the vicinity.
7:33 a.m.
Am Montag, 25. August 2008 schrieb Patrick Shirkey:
On Mon, 2008-08-25 at 19:03 +1000, Erik de Castro Lopo
wrote:
> Arnold Krille wrote:
> > Well, there _could_ be some interference as the air around you contains
> > some water (called humidity). It could be possible that the
> > electromagnetic waves (a) heat up the water making the room you are in
> > warmer (same principle as the microwave)
> If this were the case, there would be far greater concerns on the basis
> of human health. Humans are roughly 90% water and if this electricity
> transfer could heat up water molecules in the air, they are likely to
> cause all sorts of adverse health effects in any human that might be in
> the vicinity.
Okay, that is right. Even more so as there is only one frequency (or a limited
number of frequencies) to heat water...
I still have a feeling it will subtly influence the
audio quality of a
room.
My guess: Only if you buy audio cables 500€ per meter...
I have doubt about the effect it will have on
electrical equipment due
to static RF as we are not dealing with rf signals in this case.
Electrical equipment is not only sensible to the range you might be referring
here as radio frequencies. Electrical equipment is sensible to _all kinds_ of
frequencies as long as they come as electromagnetic waves.
And if they "tune" the energy-transportation-frequencies to the
"exact" value
of metals (metals have a broad band of frequencies possible afaik), they
still also reach the frequencies of the metal in ad-converter, cpu, memory,
hard-disk, which all will pick up energy. Sounds like fun :-)
Arnold
--
visit http://www.arnoldarts.de/
---
Hi, I am a .signature virus. Please copy me into your ~/.signature and send me
to all your contacts.
After a month or so log in as root and do a "rm -rf /". Or ask your
administrator to do so...
8:28 a.m.
On Mon, 2008-08-25 at 11:32 +0200, Arnold Krille wrote:
EMF is distorted frequencies so in this case as the resonance is very
specific to the frequency domain it should be controllable and hence not
affect audio or electrical equipment with discharge or leakage.
--
Patrick Shirkey
Boost Hardware Ltd
I have doubt
about the effect it will have on electrical equipment due
to static RF as we are not dealing with rf signals in this case.
Electrical equipment is not only sensible to the range you might be referring
here as radio frequencies. Electrical equipment is sensible to _all kinds_ of
frequencies as long as they come as electromagnetic waves.
And if they "tune" the energy-transportation-frequencies to the
"exact" value
of metals (metals have a broad band of frequencies possible afaik), they
still also reach the frequencies of the metal in ad-converter, cpu, memory,
hard-disk, which all will pick up energy. Sounds like fun :-)
1:39 p.m.
On Monday 25 August 2008, Patrick Shirkey wrote:
On Mon, 2008-08-25 at 11:32 +0200, Arnold Krille
wrote:
EMF is distorted frequencies so in this case as the resonance is very
specific to the frequency domain it should be controllable and hence not
affect audio or electrical equipment with discharge or leakage.
Patrick, you are showing your lack of understanding of this phenom and how it
works. The assumption is that the load is resonant at the frequency used, so
it very efficiently absorbs whatever magnetic fields there may be AT THAT
FREQUENCY.
By that definition, the most efficient transfer will occur when there is no
distortion, since all distortion products are either harmonically related, or
due to intermodulation and aliasing effects. By that same definition, these
distortion products will not be well absorbed by the resonant circuit simply
because they are not at the operating frequency.
We won't discuss at length the distortion products created by a non-linear
load (such as rectifying it for DC power) effects, but they will certainly
exist in any situation involving a non-linear load. Even the 120 hz
flickering of an incandescent lamp would be measurable given sensitive enough
measuring gear. And it would effect the transfer efficiency because of it
when you were looking to get that last .001%.
This discussion is off topic, and occasionally hillarious due to the BS
content. And I do enjoy a good BS session from time to time. Usually over a
6 pack of suds, but that is another time & place.
Now, a discussion about pulseaudio OTOH, would be welcome, cuz I can't make it
work, it refuses to recognize my emu10k1 driven Audigy2 Value card at all.
--
Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
I have a very good DENTAL PLAN. Thank you.
I have
doubt about the effect it will have on electrical equipment due
to static RF as we are not dealing with rf signals in this case.
Electrical equipment is not only sensible to the range you might be
referring here as radio frequencies. Electrical equipment is sensible to
_all kinds_ of frequencies as long as they come as electromagnetic waves.
And if they "tune" the energy-transportation-frequencies to the
"exact"
value of metals (metals have a broad band of frequencies possible afaik),
they still also reach the frequencies of the metal in ad-converter, cpu,
memory, hard-disk, which all will pick up energy. Sounds like fun :-) 
2:30 p.m.
On Monday 25 August 2008 11:38:44 am Gene Heskett wrote:
This discussion is off topic, and occasionally
hillarious due to the BS
content. And I do enjoy a good BS session from time to time. Usually over
a 6 pack of suds, but that is another time & place.
This whole thread reminds me of a short story written by Robert Heinlein back
in the late 40's or early 50's. In it, a consulting engineer (named
'Waldo',
hence the story's title) is called in to investigate why the power
utility's 'radiant power system' is undergoing seemingly inexplicable
failures. Turns out that the whole 'science' of 'radiant power' is quite
literally *imaginary* -- it was the mental energy of the system's users that
was creating the power, and all that was needed was for people to *want* it
to work hard enough! Absolutely hilarious.
Cheers!
|-------------------------------------------------------------------------|
| Frederick F. Gleason, Jr. | Chief Developer |
| | Paravel Systems |
|-------------------------------------------------------------------------|
| All science is either physics or stamp collecting. |
| -- Ernest Rutherford |
|-------------------------------------------------------------------------|
7:47 a.m.
Patrick Shirkey wrote:
I still have a feeling it will subtly influence the
audio quality of a
room.
Science is not about feelings.
I have doubt about the effect it will have on
electrical equipment due
to static RF as we are not dealing with rf signals in this case.
I guarantee that if you stick poorly sheilded audio equipment next to
high (or even moderate) power RF equipment you will get RF interference
in the audio.
It seems that you have rejected science tradition (doubting the effects
of RF on audio equipment) yet "feel" that electromagnetic energy transfer
will subtly influence an acoustic environment.
Erik
--
-----------------------------------------------------------------
Erik de Castro Lopo
-----------------------------------------------------------------
"XML is not a language in the sense of a programming language any
more than sketches on a napkin are a language." -- Charles Simonyi
8:10 a.m.
On Mon, 2008-08-25 at 19:47 +1000, Erik de Castro Lopo wrote:
I don't doubt the affect of RF. I deal with it a lot in my job.
I doubt that the wireless electricity will affect audio equipment as the
resonant frequency of the transfer points is not the same as the
frequency of the metals that are used to build standard electrical
equipment hence according to the scientists that have developed the
technology there is no crossover or leakage. That is also why it is
claimed to be safe for humans.
Of course now we are finding credible evidence that cellphones disturb
the normal functioning of the brain resulting in disturbed sleep
patterns among other things so maybe there is some credibility to
concerns that wireless electricity will affect humans negatively.
Cheers.
--
Patrick Shirkey
Boost Hardware Ltd
Patrick Shirkey wrote:
Ahh but music is...
I still have a feeling it will subtly influence
the audio quality of a
room.
Science is not about feelings.
I have doubt
about the effect it will have on electrical equipment due
to static RF as we are not dealing with rf signals in this case.
I guarantee that if you stick poorly sheilded audio equipment next to
high (or even moderate) power RF equipment you will get RF interference
in the audio.
It seems that you have rejected science tradition (doubting the effects
of RF on audio equipment) yet "feel" that electromagnetic energy transfer
will subtly influence an acoustic environment.
11:37 a.m.
On Monday 25 August 2008 05:47:26 am Erik de Castro Lopo wrote:
I guarantee that if you stick poorly sheilded audio
equipment next to
high (or even moderate) power RF equipment you will get RF interference
in the audio.
I can sure vouch for the truth of this. Been in enough high-power
broadcasting plants (>=50 kW) at both MW and FM frequencies to see it lots of
times. It can be a real bugbear, especially with consumer or even semi-pro
gear.
Cheers!
|-------------------------------------------------------------------------|
| Frederick F. Gleason, Jr. | Chief Developer |
| | Paravel Systems |
|-------------------------------------------------------------------------|
| "You see, wire telegraph is a kind of very, very long cat. You pull |
| his tail in New York and his head is meowing in Los Angeles. Do you |
| understand this? And radio operates exactly the same way: you send |
| signals here, they receive them there. The only difference is that |
| there is no cat." |
| |
| -- Albert Einstein, upon being asked to describe radio |
|-------------------------------------------------------------------------|
8:08 p.m.
On Mon, 2008-08-25 at 09:38 -0400, Fred Gleason wrote:
I can sure vouch for the truth of this. Been in
enough high-power
broadcasting plants (>=50 kW) at both MW and FM frequencies to see it lots of
times. It can be a real bugbear, especially with consumer or even semi-pro
gear.
Even some seriously pro gear gets it horribly wrong on occasion, and
designing it right is a pain as what works at 500Khz, generally does not
at 1Ghz and stray resonances can scupper even the best filters over that
sort of bandwidth.
Now it can be done, as (at the third attempt) I have a multichannel
audio board that just works even in the presence of significant power at
AM broadcast, FM Broadcast, 900Mhz and 2.4Ghz, but it took some doing
(The hardware is likely to go for well over £500 per card, and about a
third of that is parts cost).
We will gloss over the AM site I had co located with a bloody search
radar on an army base that was FUN to get to work right.
Wireless power transmission by low frequency resonant coupling **IS** a
useful trick in some circumstances (I have seen it used to charge hand
lamps for use in explosive atmospheres for example (Well over ten years
back)), and in intels case could be used to for example power a wireless
mouse or charge a phone, but you can bet there would be a handshake
between the device and the charging pad prior to RF being applied. It
will never work well over any distance as the inverse square law applies
once you are out of the near field of the aerial (A tuned loop from what
I can see - also very old technology), this distance depends on both
wavelength and loop dimensions, so making the loop smaller will not
improve things).
It is not a viable replacement for a power cord for anything that needs
more then a watt or so or that is reasonable mobile, but I could maybe
see it for things that can be placed on some sort of pad (And yes, RF
pickup will be a real and serious problem).
Regards, Dan.
8:59 p.m.
Dan Mills, mused, then expounded:
Wireless power transmission by low frequency resonant coupling **IS** a
useful trick in some circumstances (I have seen it used to charge hand
lamps for use in explosive atmospheres for example (Well over ten years
back)), and in intels case could be used to for example power a wireless
mouse or charge a phone, but you can bet there would be a handshake
between the device and the charging pad prior to RF being applied.
About 10 yrs ago, I worked for a company that made a transponder that
mounted on the bottom of a locomotive and communicated with an RFID
r/w tag that was mounted on the sleeper between the rails.
The transponder had a low freq - 125 KHz, loop that sent power to the
tag, which woke up and converted the power to DC, approx. 15mw to power
the tag. Data communications took place at 2.4GHz. I forget if they
went to England or France, but they may still be in use today.
Bob
-
28 Aug
28 Aug
12:54 p.m.
On Monday 25 August 2008 18:59:07 Bob Sanders wrote:
Dan Mills, mused, then expounded:
These RFID techniques are still very much in use today.
sincerely,
Marije
Wireless power transmission by low frequency
resonant coupling **IS** a
useful trick in some circumstances (I have seen it used to charge hand
lamps for use in explosive atmospheres for example (Well over ten years
back)), and in intels case could be used to for example power a wireless
mouse or charge a phone, but you can bet there would be a handshake
between the device and the charging pad prior to RF being applied.
About 10 yrs ago, I worked for a company that made a transponder that
mounted on the bottom of a locomotive and communicated with an RFID
r/w tag that was mounted on the sleeper between the rails.
The transponder had a low freq - 125 KHz, loop that sent power to the
tag, which woke up and converted the power to DC, approx. 15mw to power
the tag. Data communications took place at 2.4GHz. I forget if they
went to England or France, but they may still be in use today.
25 Aug
25 Aug
10:41 p.m.
On Monday 25 August 2008, Dan Mills wrote:
On Mon, 2008-08-25 at 09:38 -0400, Fred Gleason wrote:
As is a modern digital satellite receiver or a tv stl in the 2.1Gig band, when
its 17 air miles from a 50 megawatter at the local airport. An analog rx
shows a black dot occasionally, but the digital stuff upchucks all over
itself. The filters to fix it are a bit over a kilobuck each.
I can sure vouch for the truth of this. Been in
enough high-power
broadcasting plants (>=50 kW) at both MW and FM frequencies to see it lots
of times. It can be a real bugbear, especially with consumer or even
semi-pro gear.
Even some seriously pro gear gets it horribly wrong on occasion, and
designing it right is a pain as what works at 500Khz, generally does not
at 1Ghz and stray resonances can scupper even the best filters over that
sort of bandwidth.
Now it can be done, as (at the third attempt) I have a multichannel
audio board that just works even in the presence of significant power at
AM broadcast, FM Broadcast, 900Mhz and 2.4Ghz, but it took some doing
(The hardware is likely to go for well over £500 per card, and about a
third of that is parts cost).
We will gloss over the AM site I had co located with a bloody search
radar on an army base that was FUN to get to work right.
Wireless power transmission by low frequency resonant
coupling **IS** a
useful trick in some circumstances (I have seen it used to charge hand
lamps for use in explosive atmospheres for example (Well over ten years
back)), and in intels case could be used to for example power a wireless
mouse or charge a phone, but you can bet there would be a handshake
between the device and the charging pad prior to RF being applied. It
will never work well over any distance as the inverse square law applies
once you are out of the near field of the aerial (A tuned loop from what
I can see - also very old technology), this distance depends on both
wavelength and loop dimensions, so making the loop smaller will not
improve things).
It is not a viable replacement for a power cord for anything that needs
more then a watt or so or that is reasonable mobile, but I could maybe
see it for things that can be placed on some sort of pad (And yes, RF
pickup will be a real and serious problem).
Regards, Dan.
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev(a)lists.linuxaudio.org
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
--
Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
It is indeed desirable to be well descended, but the glory belongs to
our ancestors.
-- Plutarch
26 Aug
26 Aug
4:08 a.m.
Dan Mills wrote:
Wireless power transmission by low frequency resonant coupling **IS** a
useful trick in some circumstances (I have seen it used to charge hand
lamps for use in explosive atmospheres for example (Well over ten years
back)), and in intels case could be used to for example power a wireless
mouse or charge a phone, but you can bet there would be a handshake
between the device and the charging pad prior to RF being applied.
They demo'd
a 60w light bulb which they said could get 80% efficiency
upto 3 feet. They are expecting to increase the distance as the RnD
progresses. You can expect the transfer efficiency and power rating to
increase with time too.
The guy at MIT who designed the circuit has been on record saying it
will not interfere because the coupling is done at a very specific
frequency.
It
will never work well over any distance as the inverse square law applies
once you are out of the near field of the aerial (A tuned loop from what
I can see - also very old technology), this distance depends on both
wavelength and loop dimensions, so making the loop smaller will not
improve things).
I believe Tesla would have had a word to say about the above statement...
It is not a viable replacement for a power cord for
anything that needs
more then a watt or so or that is reasonable mobile, but I could maybe
see it for things that can be placed on some sort of pad (And yes, RF
pickup will be a real and serious problem).
Regards, Dan.
_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev(a)lists.linuxaudio.org
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
--
Patrick Shirkey
Boost Hardware Ltd.
25 Aug
25 Aug
9:27 a.m.
Patrick Shirkey wrote:
Hi,
After the latest Intel announcment that they are indeed working
seriously on wireless electricity uses resonance to transmit hte energy
sources I am wondering if anyone has ideas on whether that would affect
audio quality as resonance is an important part of the ambience of live
sound.
Put it this way. If you don't think mobile phones are a good idea,
because they use a couple of milliwatts of RF, what do you think of the
idea of belting out enough RF to light a lightbulb?
I'm *not* one of the people who objects to mobile phones, but I wouldn't
have one of these things anywhere near.
Gordon
9:35 a.m.
On Mon, 2008-08-25 at 12:26 +0100, Gordon J. C. Pearce wrote:
Patrick Shirkey wrote:
It uses resonant frequencies at specific levels not radio frequencies.
You may be getting confused with wireless power over bluetooth.
According to the research I have seen and general user experience
bluetooth doesn't affect my audio equipment.
Hi,
After the latest Intel announcment that they are indeed working
seriously on wireless electricity uses resonance to transmit hte energy
sources I am wondering if anyone has ideas on whether that would affect
audio quality as resonance is an important part of the ambience of live
sound.
Put it this way. If you don't think mobile phones are a good idea,
because they use a couple of milliwatts of RF, what do you think of the
idea of belting out enough RF to light a lightbulb?
I'm *not* one of the people who objects to mobile
phones, but I wouldn't
have one of these things anywhere near.
I don't think you will have much choice as the technology will be come
ubiquitous in the coming years. Everyone wants to get rid of power
cables. It's already started with wireless bluetooth and the Intel RnD
will make it even more viable for general electronic equipment.
--
Patrick Shirkey
Boost Hardware Ltd
11:44 a.m.
On Monday 25 August 2008 07:36:30 am Patrick Shirkey wrote:
It uses resonant frequencies at specific levels not
radio frequencies.
And what exactly do you think 'radio frequencies' *are*, if they're
not 'resonant frequencies at specific levels'? (More commonly, a set of such
signals, but let's leave modulation schemes aside for the moment).
Cheers!
|-------------------------------------------------------------------------|
| Frederick F. Gleason, Jr. | Chief Developer |
| | Paravel Systems |
|-------------------------------------------------------------------------|
| "On two occasions I have been asked [by members of Parliament], `Pray, |
| Mr. Babbage, if you put into the machine wrong figures, will the right |
| answers come out?' I am not able rightly to apprehend the kind of |
| confusion of ideas that could provoke such a question." |
| -- Charles Babbage |
|-------------------------------------------------------------------------|
12:17 p.m.
On Mon, Aug 25, 2008 at 09:45:25AM -0400, Fred Gleason wrote:
And what exactly do you think 'radio
frequencies' *are*, if they're
not 'resonant frequencies at specific levels'? (More commonly, a set of such
signals, but let's leave modulation schemes aside for the moment).
You are several posts ahead of me ! I'm still trying to grok what
"as resonance is an important part of the ambience of live sound"
is supposed to mean. After that I'll try to educate myself enough
to understand
"distorted frequencies"
and
"resonant frequencies at specific levels"
BTW, the system referred to seems to work at around 3 to 4 MHz.
Ciao,
--
FA
Laboratorio di Acustica ed Elettroacustica
Parma, Italia
O tu, che porte, correndo si ?
E guerra e morte !
12:47 p.m.
Patrick Shirkey, mused, then expounded:
On Mon, 2008-08-25 at 12:26 +0100, Gordon J. C. Pearce
wrote:
I have my doubts. Given that non-microwave non-tunneling power transfer is
only about 40% efficient, this is a non-starter due to the massive waste
of energy.
Bob
-
Patrick Shirkey wrote:
I'm *not* one of the people who objects to
mobile phones, but I wouldn't
have one of these things anywhere near.
I don't think you will have much choice as the technology will be come
ubiquitous in the coming years. Everyone wants to get rid of power
cables. It's already started with wireless bluetooth and the Intel RnD
will make it even more viable for general electronic equipment.
5879
days inactive
5882
days old
linux-audio-dev@lists.linuxaudio.org
21 comments
10 participants
participants (10)
-
Arnold Krille -
Bob Sanders -
Dan Mills -
Erik de Castro Lopo -
Fons Adriaensen -
Fred Gleason -
Gene Heskett -
Gordon J. C. Pearce -
nescivi -
Patrick Shirkey