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Moog frequency shifter

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October 15, 2004 9:04:47 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

DTS has just released Frank Zappa's Quaudiophiliac, which contains a
sampling of FZ's "surround" (quad) mixes from the '70's. One
particular nugget therein is an alternate mix of "Waka-Jawaka" which
has some instrument (I think it is Frank playing the guitar) through
what sounds like a ring modulator. Now on the original LP release of
Waka-Jawaka, FZ thanks Bob Moog for the use of his frequency shifter
(but this solo is absent).

I looked up the patent for the frequency shifter and found that it is
much like a ring modulator except the difference tone has been
suppressed. So it would sound something like a ring-modulator but
with only half the GRONK.

Does anyone know of other (purported or otherwise) recorded examples
of a Moog frequency shifter? And where can I get one?

More about : moog frequency shifter

Anonymous
October 16, 2004 4:33:19 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

Try here:

http://tinyurl.com/3tblz





"Gary" <midicad2001@yahoo.com> wrote in message
news:a3b3fcd7.0410151604.37ee3ef8@posting.google.com...
> DTS has just released Frank Zappa's Quaudiophiliac, which contains a
> sampling of FZ's "surround" (quad) mixes from the '70's. One
> particular nugget therein is an alternate mix of "Waka-Jawaka" which
> has some instrument (I think it is Frank playing the guitar) through
> what sounds like a ring modulator. Now on the original LP release of
> Waka-Jawaka, FZ thanks Bob Moog for the use of his frequency shifter
> (but this solo is absent).
>
> I looked up the patent for the frequency shifter and found that it is
> much like a ring modulator except the difference tone has been
> suppressed. So it would sound something like a ring-modulator but
> with only half the GRONK.
>
> Does anyone know of other (purported or otherwise) recorded examples
> of a Moog frequency shifter? And where can I get one?
Anonymous
October 16, 2004 1:10:27 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

Gary <midicad2001@yahoo.com> wrote:
>
>Does anyone know of other (purported or otherwise) recorded examples
>of a Moog frequency shifter? And where can I get one?

I don't know... But I do think Bob Moog still makes a module.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
October 16, 2004 3:32:04 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Gary"
> DTS has just released Frank Zappa's Quaudiophiliac, which contains a
> sampling of FZ's "surround" (quad) mixes from the '70's. One
> particular nugget therein is an alternate mix of "Waka-Jawaka" which
> has some instrument (I think it is Frank playing the guitar) through
> what sounds like a ring modulator. Now on the original LP release of
> Waka-Jawaka, FZ thanks Bob Moog for the use of his frequency shifter
> (but this solo is absent).
>
> I looked up the patent for the frequency shifter and found that it is
> much like a ring modulator except the difference tone has been
> suppressed. So it would sound something like a ring-modulator but
> with only half the GRONK.
>


** Wrong - a Bode frequency shifter adds or subtracts a certain number
of Hz from the input frequency. There is no modulation involved.

If the input is a tone with say 200Hz , 400Hz and 600 Hz ( like an organ
flute tone) and you set the Bode to add 50 Hz then the output will be 250Hz
, 450Hz and 650Hz - ie quite discordant.




................... Phil
Anonymous
October 16, 2004 3:32:05 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

On Sat, 16 Oct 2004 11:32:04 +1000, "Phil Allison"
<philallison@tpg.com.au> wrote:

>
>"Gary"
>> DTS has just released Frank Zappa's Quaudiophiliac, which contains a
>> sampling of FZ's "surround" (quad) mixes from the '70's. One
>> particular nugget therein is an alternate mix of "Waka-Jawaka" which
>> has some instrument (I think it is Frank playing the guitar) through
>> what sounds like a ring modulator. Now on the original LP release of
>> Waka-Jawaka, FZ thanks Bob Moog for the use of his frequency shifter
>> (but this solo is absent).
>>
>> I looked up the patent for the frequency shifter and found that it is
>> much like a ring modulator except the difference tone has been
>> suppressed. So it would sound something like a ring-modulator but
>> with only half the GRONK.
>>
>
>
> ** Wrong - a Bode frequency shifter adds or subtracts a certain number
>of Hz from the input frequency. There is no modulation involved.
>
> If the input is a tone with say 200Hz , 400Hz and 600 Hz ( like an organ
>flute tone) and you set the Bode to add 50 Hz then the output will be 250Hz
>, 450Hz and 650Hz - ie quite discordant.
>
>
>
>
>.................. Phil
>

Didn't he just say it would sounded like a ring modulator, ie quite
discordant?

He's pretty much right, that's what it sounds like.

If there's no modulation involved, what's the quadrature oscillator
doing in the circuit?


WH
October 16, 2004 9:55:46 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message news:<2tbc0lF1moknrU1@uni-berlin.de>...

> ** Wrong - a Bode frequency shifter adds or subtracts a certain number
> of Hz from the input frequency. There is no modulation involved.

Phil buddy, so HOW exactly does the frequency shifter accomplish this
"adding"?

Go ahead and elaborate on WHY a 2-output quadrature oscillator is
required instead of just a plain old single sine wave?

Also would you please explain what type of circuit would be used to
perform high quality amplitude modulation other than a multiplier, be
it 2 or 4 quadrant?

Feel free to use as much math as you like, I'll enjoy it.
Anonymous
October 16, 2004 11:50:38 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

Wallace Hastert
"Phil Allison"
>>
>> ** Wrong - a Bode frequency shifter adds or subtracts a certain number
>>of Hz from the input frequency. There is no modulation involved.
>>
>> If the input is a tone with say 200Hz , 400Hz and 600 Hz ( like an
>> organ
>>flute tone) and you set the Bode to add 50 Hz then the output will be
>>250Hz
>>, 450Hz and 650Hz - ie quite discordant.
>
> Didn't he just say it would sounded like a ring modulator, ie quite
> discordant?
>


** Modulation is another thing entirely.


> He's pretty much right, that's what it sounds like.


** Side by side, the sounds are very different.


>
> If there's no modulation involved, what's the quadrature oscillator
> doing in the circuit?


** The output signal is not "modulated" - ie not amplitude modulated nor
frequency modulated.

Shifting a frequency up or down by Harald Bode's patented method involves
the use of a 4 quadrant multiplier IC, a quadrature oscillator ( ie with
outputs 90 degrees apart ) PLUS a beast known as a Hilbert Transformer.
This is a multi section all pass filter that produces a 90 degree phase
difference across most or all the audio band.

How the hell do I know ???

I once designed a + 5 Hz Audio Frequency Shifter for howl round
suppression in PA systems.

Same basic idea - just a fixed frequency quadrature oscillator.

BTW Some foul noises are possible if you mix the original and the shifted
sounds !






........... Phil
October 16, 2004 11:50:39 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message news:<2tc97eF1tnvr0U1@uni-berlin.de>...

> > If there's no modulation involved, what's the quadrature oscillator
> > doing in the circuit?
>
>
> ** The output signal is not "modulated" - ie not amplitude modulated nor
> frequency modulated.

Phil,
You left out phase and waveshape modulation. OK so a ring modulator
really works on a 4-quadrant multiplier, BFD, it's still commonly
called a ring modulator, I did not invent this.

However, in the interest of taking advantage of your IMMENSE SUPERIOR
TO EVERYONE IN THE KNOWN UNIVERSE knowledge, what are the important
differences between the frequency shifter and what is commonly known
right wrong or otherwise as a ring modulator. I'm really interested
to know.

Do you have side by side sound samples to offer us to show that really
they sound nothing alike?
Anonymous
October 17, 2004 1:13:42 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

If memory serves, and my electronic music buddies and I in high school
discussed this a lot, a ring modulator takes two signals, and multiplies
them together. If one wave is 2 * sin(t) and another is 3 * sin(2*t) then a
ring modulator generates the signal (2*sin(t)) * (3*sin(2*t)) from the two.
when setup correctly, this tends to produce a ringing effect on the sounds,
like a metallic high pitched gong, and hence the name. This requires a
special circuit. I don't know of any way to do this with just two
voltagee-controlled oscillators alone, with any combination of same plus
filters and amplifiers. A friend of mine in high school figured out that
one way to do it was to use a transformer with three windings. Two windings
would be for the inputs and the third was the output. It seemed to work.

Frequency shifting, I thought, was the same as FM (frequency modulation).
The frequency of one sound is changed in some way by the signal from another
sound. One way to do it is simply to channel the output of one
voltage-controlled oscillator into the voltage-control input of another.
This is probably the simplest way to do it. Where this is not possible,
such as doing this to a human voice input, you need special circuits to do
it. To my ears the effects are similar at times, but both are also capable
of generating sounds that you cannot get any other way, and both can sound
quite different from one another.

I have generated MP3s that show off both effects - they do sound similar but
they are also definitely different! They're too large to upload to my
website right now, so if you want them and can handle about 700K, send me
email and I'll attach them to my reply.

Hope this clears the air, and if it doesn't, hope the addition of fuel won't
let the fire burn out of control. ^_^

--
Sincerely,
--- Dave
----------------------------------------------------------------------
It don't mean a thing
unless it has that certain "je ne sais quoi"
Duke Ellington
----------------------------------------------------------------------

"Gary" <midicad2001@yahoo.com> wrote in message
news:a3b3fcd7.0410160951.1f22447c@posting.google.com...
> "Phil Allison" <philallison@tpg.com.au> wrote in message
> news:<2tc97eF1tnvr0U1@uni-berlin.de>...
>
>> > If there's no modulation involved, what's the quadrature oscillator
>> > doing in the circuit?
>>
>>
>> ** The output signal is not "modulated" - ie not amplitude modulated
>> nor
>> frequency modulated.
>
> Phil,
> You left out phase and waveshape modulation. OK so a ring modulator
> really works on a 4-quadrant multiplier, BFD, it's still commonly
> called a ring modulator, I did not invent this.
>
> However, in the interest of taking advantage of your IMMENSE SUPERIOR
> TO EVERYONE IN THE KNOWN UNIVERSE knowledge, what are the important
> differences between the frequency shifter and what is commonly known
> right wrong or otherwise as a ring modulator. I'm really interested
> to know.
>
> Do you have side by side sound samples to offer us to show that really
> they sound nothing alike?
October 17, 2004 1:13:43 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

Since this seems to have generated some interest, here's a link to the
Moog patents:

http://www.till.com/articles/moog/patents.html

The second one down is the gadget I'm talking about. I'll let you
read it yourselves, but I will quote this little part here:

"It's important to note that this effect is a frequency shift and not
the pitch shift effect currently available in modern digital effects
boxes. In a frequency shifter all frequency components of the input
signal are offset by a specific number of Hz while in a pitch shifter
all frequency components are multiplied by a specific factor. The
former sounds something like a ring modulator while the latter sound
something like playing back a tape at a different speed."

It's almost impossible to understand why it sounds the way it does
without resorting to mathematics.
Anonymous
October 17, 2004 4:31:13 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

Here are samples from the Bode / Moog frequency shifter

http://www.surrealstudios.com/freq-out/


They should be self explanatory -

Basic sample and versions through the frequency shifter.
There is one example where it is shifted through the entire frequency
spectrum, and unsurprisingly it sounds like a ring modulator.

But it's not.

The barberpole example is mixed with the original signal. It's pretty
darn cool.

Have fun. I'm going to bed.







Kurt Riemann
Anonymous
October 17, 2004 11:39:46 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

midicad2001@yahoo.com (Gary) wrote in news:a3b3fcd7.0410151604.37ee3ef8
@posting.google.com:

> I looked up the patent for the frequency shifter and found that it is
> much like a ring modulator except the difference tone has been
> suppressed. So it would sound something like a ring-modulator but
> with only half the GRONK.

I think the answer is fairly straightforward mathematically but it depends
on superimposed sine waves having the characteristic through the process
that (A + B)(R) = A(R) + B(R). Where (R) is the ring modulator function.
If (R) is just multiplication times a carrier, I think it is valid.

Freq shifter

Input = A + B, e.g. 500 Hz + 1,000 Hz (1st overtone)
Carrier = 175 Hz.

Output = 675 + 1175 (75 Hz short of 1st overtone)

Ring modulator:
Input = A + B, e.g. 500 Hz + 1,000 Hz (1st overtone)
Carrier = 175 Hz.

Output = 325 Hz + 675 Hz + 825 Hz + 1175 Hz. Yes? NO?

The ring modulator output has two additional spectral components. But it
also shares two spectral components and in general the frequency shifter
would have half the components of the ring modulator but they would
overlap. Does this mean they might sound in some way similar? yes? No?
How many gum chewing twins who do chew gum would think so?

This is not to say that with a low freq carrier SAY LIKE 5 Hz or so, a freq
shifter would/could be unnoticeable. I'm just imagining putting a pitch
shift of a third on the choir with a loop delay about 3 seconds and see
what happens!

Does any freq shifter/ring mod device offer both upper and/or lower
sidebands?
Anonymous
October 17, 2004 2:48:25 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Gary"
> "Phil Allison"
>
>> > If there's no modulation involved, what's the quadrature oscillator
>> > doing in the circuit?
>>
>>
>> ** The output signal is not "modulated" - ie not amplitude modulated
>> nor
>> frequency modulated.
>

> You left out phase and waveshape modulation.


** So ?? It is not them either.


> However, in the interest of taking advantage of your IMMENSE SUPERIOR
> TO EVERYONE IN THE KNOWN UNIVERSE knowledge, what are the important
> differences between the frequency shifter and what is commonly known
> right wrong or otherwise as a ring modulator. I'm really interested
> to know.
>


** Errrr - one is a modulator while the other is not.


> Do you have side by side sound samples to offer us to show that really
> they sound nothing alike?


** Imagine a steady, pure tone is fed into a frequency shifter - the
output is also a steady, pure tone but at some higher or lower frequency.
That is nothing like a modulator.




............... Phil
Anonymous
October 17, 2004 4:09:21 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Gary"
> "Phil Allison"


** Replacing the missing context that Gary maliciously snipped:

> I looked up the patent for the frequency shifter and found that it is
> much like a ring modulator except the difference tone has been
> suppressed. So it would sound something like a ring-modulator but
> with only half the GRONK.
>

>> ** Wrong - a Bode frequency shifter adds or subtracts a certain
>> number
>> of Hz from the input frequency. There is no modulation involved.
>
> Phil buddy, so HOW exactly does the frequency shifter accomplish this
> "adding"?


** You have misread my post and ignored my subsequent comments.

There is "no modulation involved" in the output signal from a frequency
shifter.

A pure tone comes out still a pure tone but with a new frequency.




............. Phil
Anonymous
October 17, 2004 4:09:22 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in
news:2te2igF1smg45U1@uni-berlin.de:

>
> "Gary"
>> "Phil Allison"
>
>
> ** Replacing the missing context that Gary maliciously snipped:

Oh yeah I'm SO malicious! 8^) GRRRRR now aren't you scared. Anyone with
a news reader can figure out what you originally posted.

>> I looked up the patent for the frequency shifter and found that it is
>> much like a ring modulator except the difference tone has been
>> suppressed. So it would sound something like a ring-modulator but
>> with only half the GRONK.
>>
>
>>> ** Wrong - a Bode frequency shifter adds or subtracts a certain
>>> number
>>> of Hz from the input frequency. There is no modulation involved.
>>
>> Phil buddy, so HOW exactly does the frequency shifter accomplish this
>> "adding"?
>
> ** You have misread my post and ignored my subsequent comments.

You ignored my other questions too, I won't hold it against you though.

> There is "no modulation involved" in the output signal from a
> frequency shifter.

You mean there's no amplitude or frequency modulation PRESENT in the
output signal? As in tremolo or vibrato? That I would agree with. But
there sure as heck is modulation involved in the CREATION of this sound,
and other than the suppression of the difference tone, it is quite
similar to a ring modulator.

> A pure tone comes out still a pure tone but with a new frequency.

Whereas a ring modulator (fill in the blank).

I did find it interesting that you used one to avoid PA feedback. You do
acknowledge that adding the same frequency shift to a given set of
harmonically related components would cause them to no longer be
perfectly harmonically related?

For example, a low E on a bass guitar is about 41 Hz, at 46 Hz you
shifted that almost up to an F sharp! The first harmonic at 83 would now
be at 88, which is just over F. That would sound pretty bad I think.
Not that music consists just of people playing low E on the bass, but you
get my drift. The higher the frequencies involved the less you'd notice
it. So if it were just for vocals I could see getting away with it.

Here's my reference.
http://www.contrabass.com/pages/frequency.html

Did you use this on the mains or the monitors? You REALLY did this?

aka
Gary
Anonymous
October 17, 2004 4:09:23 PM

Archived from groups: rec.audio.pro (More info?)

Digital Larry wrote:

> I did find it interesting that you used one to avoid PA feedback. You do
> acknowledge that adding the same frequency shift to a given set of
> harmonically related components would cause them to no longer be
> perfectly harmonically related?

Music, schmooozik, who cares?

> For example, a low E on a bass guitar is about 41 Hz, at 46 Hz you
> shifted that almost up to an F sharp! The first harmonic at 83 would now
> be at 88, which is just over F. That would sound pretty bad I think.

A major seventh with stretch marks.

--
ha
Anonymous
October 17, 2004 5:25:12 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Gary"
> Since this seems to have generated some interest, here's a link to the
> Moog patents:
>
> http://www.till.com/articles/moog/patents.html
>
> The second one down is the gadget I'm talking about. I'll let you
> read it yourselves, but I will quote this little part here:
>
> "It's important to note that this effect is a frequency shift and not
> the pitch shift effect currently available in modern digital effects
> boxes. In a frequency shifter all frequency components of the input
> signal are offset by a specific number of Hz while in a pitch shifter
> all frequency components are multiplied by a specific factor. The
> former sounds something like a ring modulator while the latter sound
> something like playing back a tape at a different speed."



** That is a quote from some dude called J Donald Tillman ????





............. Phil
Anonymous
October 17, 2004 5:25:13 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in news:2te70nF1ucshkU1@uni-
berlin.de:


>
> ** That is a quote from some dude called J Donald Tillman ????

Yeah he's sure got a lotta nerve huh.
Anonymous
October 17, 2004 6:11:18 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Digital Larry"
> "Phil Allison"
>>
>> ** Replacing the missing context that Gary maliciously snipped:
>
> Oh yeah I'm SO malicious! 8^) GRRRRR now aren't you scared. Anyone with
> a news reader can figure out what you originally posted.
>

** Then what was your dumb excuse for getting it wrong ????


>>> I looked up the patent for the frequency shifter and found that it is
>>> much like a ring modulator except the difference tone has been
>>> suppressed. So it would sound something like a ring-modulator but
>>> with only half the GRONK.
>>>
>>
>>>> ** Wrong - a Bode frequency shifter adds or subtracts a certain
>>>> number of Hz from the input frequency. There is no modulation involved.
>>>
>>> Phil buddy, so HOW exactly does the frequency shifter accomplish this
>>> "adding"?
>>
>> ** You have misread my post and ignored my subsequent comments.
>
> You ignored my other questions too,


** Since that all derived from your misreading and smartarse attitude.



>> There is "no modulation involved" in the output signal from a
>> frequency shifter.
>
> You mean there's no amplitude or frequency modulation PRESENT in the
> output signal? As in tremolo or vibrato? That I would agree with. But
> there sure as heck is modulation involved in the CREATION of this sound,
> and other than the suppression of the difference tone, it is quite
> similar to a ring modulator.
>
>> A pure tone comes out still a pure tone but with a new frequency.
>
> Whereas a ring modulator (fill in the blank).
>

** Creates additional sideband frequencies by amplitude modulation.


> I did find it interesting that you used one to avoid PA feedback.


** The technique has been in wide use since the early 1960s when it was
first implemented with valves.


> You do
> acknowledge that adding the same frequency shift to a given set of
> harmonically related components would cause them to no longer be
> perfectly harmonically related?


** The shift is small enough for that to be not very noticeable.


> For example, a low E on a bass guitar is about 41 Hz, at 46 Hz you
> shifted that almost up to an F sharp! The first harmonic at 83 would now
> be at 88, which is just over F. That would sound pretty bad I think.


** Every instrument on a recording gets shifted up together.


> Not that music consists just of people playing low E on the bass, but you
> get my drift.


** I see your error - it is one of the common ones people dream up when
they have never heard a shifter.

> The higher the frequencies involved the less you'd notice it.


** Ears judge apparent pitch from the highest harmonics of a musical
ote - these are mostly in the range of 500 Hz to 3000 Hz so a 5 Hz up
shift no more than 1% and almost undetectable.


> Did you use this on the mains or the monitors?


** The main application is for public speaking in reverberant rooms - ie
a PA system in a hall or a church. It can be used for vocal monitors in a
SR application - but only if the stage area is very reverberant will it
help at all.

Frequency shifting offers no benefit against direct, or short path,
acoustic feedback but dramatically reduces the aggravating effect of
reverberation. System gain can be increased by 8 dB or more in typical
churches and halls and even then *no howling happens* - just a slight
warble in the sound lets you know the upper limit has been reached.

Naturally, there are no adjustments to get right ( other than the up shift
frequency) and it works equally well at any audio frequency.



.............. Phil
Anonymous
October 17, 2004 6:11:19 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

Does anyone have wav/mp3 samples of before and after processing with
the frequency shifter? I'm curious how these things work, do they change
the time of the sample you send thru them, like if you were to pitch
up a wav file in the piano roll of a sequencer?
Anonymous
October 17, 2004 6:11:19 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in
news:2te9rkF1uas94U1@uni-berlin.de:

>
> "Digital Larry"
>> "Phil Allison"
>>>
>>> ** Replacing the missing context that Gary maliciously snipped:
>>
>> Oh yeah I'm SO malicious! 8^) GRRRRR now aren't you scared. Anyone
>> with a news reader can figure out what you originally posted.
>>
>
> ** Then what was your dumb excuse for getting it wrong ????
>
>
>>>> I looked up the patent for the frequency shifter and found that it
>>>> is much like a ring modulator except the difference tone has been
>>>> suppressed. So it would sound something like a ring-modulator but
>>>> with only half the GRONK.
>>>>
>>>
>>>>> ** Wrong - a Bode frequency shifter adds or subtracts a
>>>>> certain
>>>>> number of Hz from the input frequency. There is no modulation
>>>>> involved.
>>>>
>>>> Phil buddy, so HOW exactly does the frequency shifter accomplish
>>>> this "adding"?
>>>
>>> ** You have misread my post and ignored my subsequent comments.
>>
>> You ignored my other questions too,
>
>
> ** Since that all derived from your misreading and smartarse
> attitude.
>
>
>
>>> There is "no modulation involved" in the output signal from a
>>> frequency shifter.
>>
>> You mean there's no amplitude or frequency modulation PRESENT in the
>> output signal? As in tremolo or vibrato? That I would agree with.
>> But there sure as heck is modulation involved in the CREATION of this
>> sound, and other than the suppression of the difference tone, it is
>> quite similar to a ring modulator.
>>
>>> A pure tone comes out still a pure tone but with a new frequency.
>>
>> Whereas a ring modulator (fill in the blank).
>>
>
> ** Creates additional sideband frequencies by amplitude modulation.
>
>
>> I did find it interesting that you used one to avoid PA feedback.
>
>
> ** The technique has been in wide use since the early 1960s when it
> was first implemented with valves.
>
>
>> You do
>> acknowledge that adding the same frequency shift to a given set of
>> harmonically related components would cause them to no longer be
>> perfectly harmonically related?
>
>
> ** The shift is small enough for that to be not very noticeable.

But if you DO set the carrier to something like 500 Hz, or 1000 Hz, the
same setting (e.g.) on a ring modulator, and put in some sound, you say
that the result is NOTHING like a ring modulator? How would you describe
it then? Because that is a very characteristic sound which can
obliterate the original except for rhythm.

Are you saying that a frequency shifter CAN be transparent, or it's
ALWAYS transparent, regardless of the carrier frequency? I believe what
you say about a small shift in the application you described. And OK I
haven't heard or experimented with one so that's why I ask the question.

>> For example, a low E on a bass guitar is about 41 Hz, at 46 Hz you
>> shifted that almost up to an F sharp! The first harmonic at 83 would
>> now be at 88, which is just over F. That would sound pretty bad I
>> think.
>
>
> ** Every instrument on a recording gets shifted up together.

[snip]
** I see your error - it is one of the common ones people dream up
> when they have never heard a shifter.
[snip]
> ** Ears judge apparent pitch from the highest harmonics of a musical
> ote - these are mostly in the range of 500 Hz to 3000 Hz so a 5 Hz
> up shift no more than 1% and almost undetectable.

OK but are you really saying that a 5 Hz shift would have no audible
effect on a low bass E note? Have you tried it? I haven't that is why I
ask.








>
>> Did you use this on the mains or the monitors?
>
>
> ** The main application is for public speaking in reverberant rooms
> - ie a PA system in a hall or a church. It can be used for vocal
> monitors in a SR application - but only if the stage area is very
> reverberant will it help at all.
>
> Frequency shifting offers no benefit against direct, or short path,
> acoustic feedback but dramatically reduces the aggravating effect of
> reverberation. System gain can be increased by 8 dB or more in
> typical churches and halls and even then *no howling happens* - just
> a slight warble in the sound lets you know the upper limit has been
> reached.
>
> Naturally, there are no adjustments to get right ( other than the up
> shift
> frequency) and it works equally well at any audio frequency.
>
>
>
> ............. Phil
>
>
>
>
Anonymous
October 17, 2004 6:11:19 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in
news:2te9rkF1uas94U1@uni-berlin.de:


>>> A pure tone comes out still a pure tone but with a new frequency.
>>
>> Whereas a ring modulator (fill in the blank).
>>
> ** Creates additional sideband frequencies by amplitude modulation.

Example 1:

Freq shifter.

Input = 5000 Hz.
Carrier = 500 Hz

Output = ?

Example 2.

Ring Modulator
Input = 5000 Hz.
Carrier = 500 Hz

Output = ?
Anonymous
October 17, 2004 6:52:56 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"dinkmeister"

> Does anyone have wav/mp3 samples of before and after processing with
> the frequency shifter?


** I have some music files ( from commercial CDs) that were shifted by +5
Hz - very hard to tell any difference.

> I'm curious how these things work, do they change
> the time of the sample you send thru them,


** No way - it is simple analogue signal processing.





............ Phil
Anonymous
October 17, 2004 8:33:14 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Digital Larry"
> "Phil Allison"

**Back goes the context :

> Since this seems to have generated some interest, here's a link to the
> Moog patents:
>
> http://www.till.com/articles/moog/patents.html
>
> The second one down is the gadget I'm talking about. I'll let you
> read it yourselves, but I will quote this little part here:
>
> "It's important to note that this effect is a frequency shift and not
> the pitch shift effect currently available in modern digital effects
> boxes. In a frequency shifter all frequency components of the input
> signal are offset by a specific number of Hz while in a pitch shifter
> all frequency components are multiplied by a specific factor. The
> former sounds something like a ring modulator while the latter sound
> something like playing back a tape at a different speed."


>> ** That is a quote from some dude called J Donald Tillman ????
>
> Yeah he's sure got a lotta nerve huh.


** The guy with the nerve is YOU in not saying who the quote was REALLLY
from.

You pretended it was from Moog.




............. Phil
Anonymous
October 17, 2004 8:33:15 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in
news:2tei1aF1u51lvU1@uni-berlin.de:

>>> ** That is a quote from some dude called J Donald Tillman ????
>>
>> Yeah he's sure got a lotta nerve huh.
>
>
> ** The guy with the nerve is YOU in not saying who the quote was
> REALLLY from.
>
> You pretended it was from Moog.
>

If I wanted to pretend it was from Moog maybe I would have given it an
attribution. C'mon Phil. I mean great detective work, you have exposed me
for the fraud I am. Another 5 points for you. What tipped you off that it
wasn't from Moog? I know you're a grown up person but that is just silly.

Somebody named J. Donald Tillman who I don't know from Adam and is probably
a terrorist or something (sarcasm) made a claim that a freq shifter could
sound like a ring modulator, all of which is clearly in the ear of the
beholder anyway. Happy?

By the way I am enjoying this.
Anonymous
October 17, 2004 9:10:55 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Digital Larry"
> "Phil Allison"

**Back goes the context AGAIN :

> Since this seems to have generated some interest, here's a link to the
> Moog patents:
>
> http://www.till.com/articles/moog/patents.html
>
> The second one down is the gadget I'm talking about. I'll let you
> read it yourselves, but I will quote this little part here:
>
> "It's important to note that this effect is a frequency shift and not
> the pitch shift effect currently available in modern digital effects
> boxes. In a frequency shifter all frequency components of the input
> signal are offset by a specific number of Hz while in a pitch shifter
> all frequency components are multiplied by a specific factor. The
> former sounds something like a ring modulator while the latter sound
> something like playing back a tape at a different speed."


>>>> ** That is a quote from some dude called J Donald Tillman ????
>>>
>>> Yeah he's sure got a lotta nerve huh.
>>
>>
>> ** The guy with the nerve is YOU in not saying who the quote was
>> REALLY from.
>>
>> You pretended it was from Moog.
>>
>
> If I wanted to pretend it was from Moog maybe I would have given it an
> attribution.


** Anyone can see you effectively attributed it to Moog.


> By the way I am enjoying this.



** Public masturbators like you usually do.



............. Phil
Anonymous
October 17, 2004 9:10:56 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in news:2tek7uF1tn4rcU1@uni-
berlin.de:


> ** Anyone can see you effectively attributed it to Moog.

If anyone else really feels that way I apologize.
October 17, 2004 9:10:57 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

Kurt Riemann <> wrote in message news:<8le4n0de6al3kqiaao5lfakn1s75gjbdl8@4ax.com>...

>
> You never have to apologize because of anything Phil says.

Oh I knew full well who he has when I started into it. I did learn a
couple things though, #1 the use of said device as brute force
feedback prevention #2 he hasn't changed a bit!
Anonymous
October 17, 2004 9:10:57 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

Digital Larry wrote:

> > ** Anyone can see you effectively attributed it to Moog.

> If anyone else really feels that way I apologize.

Consider that ol' Assilon isn't just anyone, and appreciate that lots of
somebodies saw no attempt on your part to attribute the quote to Moog.
It's a reading-for-content thing.

--
ha
Anonymous
October 17, 2004 9:30:06 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Digital Larry"
"Phil Allison"
>>>
>>> I did find it interesting that you used one to avoid PA feedback.
>>
>> ** The technique has been in wide use since the early 1960s when it
>> was first implemented with valves.
>>
>>> You do
>>> acknowledge that adding the same frequency shift to a given set of
>>> harmonically related components would cause them to no longer be
>>> perfectly harmonically related?
>>
>>
>> ** The shift is small enough for that to be not very noticeable.
>
> But if you DO set the carrier to something like 500 Hz, or 1000 Hz,


** Way off the subject.

>
> Are you saying that a frequency shifter CAN be transparent,


** I said just what I wrote - you do have trouble reading.


>>> For example, a low E on a bass guitar is about 41 Hz, at 46 Hz you
>>> shifted that almost up to an F sharp! The first harmonic at 83 would
>>> now be at 88, which is just over F. That would sound pretty bad I
>>> think.
>>

> ** I see your error - it is one of the common ones people dream up
>> when they have never heard a shifter.

>> ** Ears judge apparent pitch from the highest harmonics of a musical
>> ote - these are mostly in the range of 500 Hz to 3000 Hz so a 5 Hz
>> up shift no more than 1% and almost undetectable.
>
> OK but are you really saying that a 5 Hz shift would have no audible
> effect on a low bass E note? Have you tried it? I haven't that is why I
> ask.


** Since there is no need to ever use a 5 Hz frequency shifter with a bass
guitar the issue never arises.

When a + 5Hz shift is applied to a variety of recorded music most listeners
cannot tell there is any change.



" ** The main application is for public speaking in reverberant rooms
- ie a PA system in a hall or a church. It can be used for vocal
monitors in a SR application - but only if the stage area is very
reverberant will it help at all. "


** So you ignored all this ????





.............. Phil
Anonymous
October 17, 2004 9:30:07 PM

Archived from groups: rec.audio.pro (More info?)

Kurt Riemann wrote:

> You don't think most
> people could hear the shifted harmonics? It makes my eyes pop out. My
> dog left the control room while I did the example.

Your dog's mind is vastly superior to the asterisk burdened cranial
vacuum of the unit with which you attempt discourse. Moreover, your dog
has ears.

--
ha
October 17, 2004 9:30:07 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

Phil Allison wrote:
>
> What I said was:
>
> " When a + 5Hz shift is applied to a variety of recorded music most
> listeners
> cannot tell there is any change. "

So post a sample and let *us* decide!
Anonymous
October 17, 2004 9:30:07 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

On Sun, 17 Oct 2004 23:12:17 +1000, "Phil Allison"
<philallison@tpg.com.au> wrote:


>** I just told you dickhead - a dedicated 5 Hz shifter of high quality
>for PA system use.
>
> Not an antique Moog effects unit probably way out of alignment.
>

Nope. It is a custom built Bode Frequency shifter built for me by
Harald Bode shortly before his death.


>
>** It is an effects unit.
>

Nope. It's a Frequency Shifter.

>
>> Well, smartass, just take my unshifted example and run it through your
>> "high quality" dedicated +5 Hz audio frequency shifter and post it.
>>
>
>
>** Your "sample" is a disgusting noise - sounds like a $5 squeeze box.
>
>

Nope. The sample has plenty of harmonics and they shift exactly as
specified.


Gee Phil. Maybe it would be best for you to post a sterling example of
your own fabulous frequency shifter.




Kurt Riemann
Anonymous
October 17, 2004 9:30:08 PM

Archived from groups: rec.audio.pro (More info?)

On Sun, 17 Oct 2004 15:46:31 GMT, walkinay@thegrid.net (hank alrich)
wrote:

>Kurt Riemann wrote:
>
>> You don't think most
>> people could hear the shifted harmonics? It makes my eyes pop out. My
>> dog left the control room while I did the example.

Anyway, it was fun to dust off the unit again. Despite any of Phil's
rantings about it being an "effects unit", it does exactly what we are
talking about without artifacts. Look at the waveforms or do a
spectral analysis; it's spot on.

The examples I posted are accurate.

AND it can sound like a ring modulator to the uninitiated when pushed
to the extreme.

And it gets under Phil's skin that frequency shifting has these kinds
of sonic signatures. That's worth the price of admission right there.

>
>Your dog's mind is vastly superior to the asterisk burdened cranial
>vacuum of the unit with which you attempt discourse. Moreover, your dog
>has ears.


Kurt Riemann
Anonymous
October 17, 2004 9:32:50 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Digital Larry"
> "Phil Allison"

>>>> A pure tone comes out still a pure tone but with a new frequency.
>>>
>>> Whereas a ring modulator (fill in the blank).
>>>
>> ** Creates additional sideband frequencies by amplitude modulation.
>
> Example 1:
>
> Freq shifter.
>
> Input = 5000 Hz.
> Carrier = 500 Hz
>
> Output = ?


** 5500Hz ( or 4500 Hz) but not both


> > Example 2.
>
> Ring Modulator
> Input = 5000 Hz.
> Carrier = 500 Hz
>
> Output = ?


** 4500 Hz , 5000 Hz and 5500 Hz .




............. Phil
October 18, 2004 12:27:28 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message news:<2telh1F1usg03U1@uni-berlin.de>...
> "Digital Larry"
> > "Phil Allison"

> > Example 1:
> >
> > Freq shifter.
> >
> > Input = 5000 Hz.
> > Carrier = 500 Hz
> >
> > Output = ?
>
>
> ** 5500Hz ( or 4500 Hz) but not both

OK.

> > > Example 2.
> >
> > Ring Modulator
> > Input = 5000 Hz.
> > Carrier = 500 Hz
> >
> > Output = ?
>
>
> ** 4500 Hz , 5000 Hz and 5500 Hz .

If trimmed properly no input or carrier should exist in the output.
October 18, 2004 1:08:03 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

Kurt Riemann <> wrote in message news:<psa4n0pgp6kbfum9ic27qc6v61b4jut0l2@4ax.com>...
> Here are samples from the Bode / Moog frequency shifter
>
> http://www.surrealstudios.com/freq-out/
> They should be self explanatory -

Thanks!

>
> Basic sample and versions through the frequency shifter.
> There is one example where it is shifted through the entire frequency
> spectrum, and unsurprisingly it sounds like a ring modulator.
>
> But it's not.

Here's a link to the Moog/Bode patent:
http://tinyurl.com/48dh8

Seems like it actually uses TWO multipliers, aka ring modulators,
using the quadrature stuff to generate a signal allowing you to cancel
the difference tones. I find this circuit to be exceptionally clever!
Anonymous
October 18, 2004 1:34:11 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

<Kurt Riemann
"Phil Allison"

>>> Not that music consists just of people playing low E on the bass, but
>>> you
>>> get my drift.

>>** I see your error - it is one of the common ones people dream up when
>>they have never heard a shifter.
>
> I see your answer.


** But have not the tiniest damn clue what it is saying.



>>** Ears judge apparent pitch from the highest harmonics of a musical
>>note - these are mostly in the range of 500 Hz to 3000 Hz so a 5 Hz up
>>shift no more than 1% and almost undetectable.
>>
>
> Oh really?


** No surprise that a moron like you has never read up on the topic.



> Here's what Phil thinks is "almost undetectable."


** Total lie from a complete ass.




........... Phil
Anonymous
October 18, 2004 1:34:12 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

On Sun, 17 Oct 2004 21:34:11 +1000, "Phil Allison"
<philallison@tpg.com.au> wrote:


>
>> Here's what Phil thinks is "almost undetectable."
>
>
> ** Total lie from a complete ass.
>

I'm confused, is it or isn't it detectable?

It's the circuit you were talking about, doing the thing you
described.

Is this what you describe as "almost undetectable?"


Kurt Riemann
Anonymous
October 18, 2004 2:30:26 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

<Kurt Riemann
"Phil Allison"

>>> Here's what Phil thinks is "almost undetectable."
>>
>> ** Total lie from a complete ass.
>>
>
> I'm confused, is it or isn't it detectable?


** You are genetically, permanently confused.


> It's the circuit you were talking about,


** No it is not the device related to my comments - which was a *high
quality*,
dedicated + 5 Hz audio frequency shifter.

Polyfusion make a similar unit - the model 745.

The Moog /Bode was never intended or designed for such an application.





............ Phil
Anonymous
October 18, 2004 2:30:27 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

On Sun, 17 Oct 2004 22:30:26 +1000, "Phil Allison"
<philallison@tpg.com.au> wrote:

>
><Kurt Riemann
> "Phil Allison"
>
>>>> Here's what Phil thinks is "almost undetectable."
>>>
>>> ** Total lie from a complete ass.
>>>
>>
>> I'm confused, is it or isn't it detectable?
>
>
>** You are genetically, permanently confused.
>
>
>> It's the circuit you were talking about,
>
>
>** No it is not the device related to my comments - which was a *high
>quality*,
>dedicated + 5 Hz audio frequency shifter.
>
> Polyfusion make a similar unit - the model 745.
>
>The Moog /Bode was never intended or designed for such an application.
>
>
>
>
>
> ............ Phil
>
>

Do stop pasting your replies from your other posts, it makes you sound
like a parrot.

There is nothing wrong with the example, Phil, and you know it. The
Bode is a high-quality unit. The Pink Noise example proves the
response of the unit is excellent.

If you won't address the examples, then I'm left with only two
possible conclusions -

1. Phil is *gasp* wrong about whether or not this is audible -

or

2. Phil can't tell the difference.


(There is a third possibility, but we already know what it is . . .)





Kurt Riemann
Anonymous
October 18, 2004 2:30:28 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Ed Edelenbos" <eded@spameasy.net> wrote in news:f8idnZIzeuuOGu_cRVn-
uA@speakeasy.net:

> It sure would be nice if the lot of you took a little time off from this
> exchange to grow up.

Ed, did you ever see an episode of the Andy Griffith show where he taught a
couple to stop arguing after years of steady conflict?

It turned out that they really enjoyed arguing. That's what's going on
here. It has nothing to do with right or wrong and everything to do with
the competition.

You just have to ignore them and let them play with themselves.
Anonymous
October 18, 2004 2:30:28 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:2tfgvuF1rv9jmU1@uni-berlin.de...
>
> "Ed Edelenbos"
>> It sure would be nice if the lot of you took a little time off from this
>> exchange to grow up.
>>
>> Ed
>
>
> ** Another bully pops his ugly head up out of the dunny.
>

Awww, poor Phil. Act like one and get treated like one?

PLONK

Ed
Anonymous
October 18, 2004 2:30:29 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Carey Carlan" <gulfjoe@hotmail.com> wrote in message
news:Xns95857C0CD6BBCgulfjoehotmailcom@207.69.189.191...
> "Ed Edelenbos" <eded@spameasy.net> wrote in news:f8idnZIzeuuOGu_cRVn-
> uA@speakeasy.net:
>
>> It sure would be nice if the lot of you took a little time off from this
>> exchange to grow up.
>
> Ed, did you ever see an episode of the Andy Griffith show where he taught
> a
> couple to stop arguing after years of steady conflict?
>
> It turned out that they really enjoyed arguing. That's what's going on
> here. It has nothing to do with right or wrong and everything to do with
> the competition.
>
> You just have to ignore them and let them play with themselves.

I know... thanks for the return to reality.

Ed
Anonymous
October 18, 2004 3:37:22 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

On 17 Oct 2004 21:08:03 -0700, midicad2001@yahoo.com (Gary) wrote:

>Kurt Riemann <> wrote in message news:<psa4n0pgp6kbfum9ic27qc6v61b4jut0l2@4ax.com>...
>> Here are samples from the Bode / Moog frequency shifter
>>
>> http://www.surrealstudios.com/freq-out/
>> They should be self explanatory -
>
>Thanks!
>
>>
>> Basic sample and versions through the frequency shifter.
>> There is one example where it is shifted through the entire frequency
>> spectrum, and unsurprisingly it sounds like a ring modulator.
>>
>> But it's not.
>
>Here's a link to the Moog/Bode patent:
>http://tinyurl.com/48dh8
>
>Seems like it actually uses TWO multipliers, aka ring modulators,
>using the quadrature stuff to generate a signal allowing you to cancel
>the difference tones. I find this circuit to be exceptionally clever!

In the Bode there is a + and - output and a way to mix them on the
front panel. So when you are in (I believe) linear mode you have
opposite output frequencies - upshift and downshift harmonics -
available.

It's a cool device, I use it a lot when I transfer midi tracks one at
a time to hard disk fo create a very unique snarl.

It's fun on a recursive delay at low mod frequencies, too. Each repeat
shifts the frequency more.

Interestingly, with anything with a chiff attack is phased up or down
identically on each note, unlike a phaser or flanger which varies in
tone depending on where the modulator is.



Kurt Riemann
Anonymous
October 18, 2004 5:20:02 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Gary"
> Kurt Riemann
>
>>
>> You never have to apologize because of anything Phil says.
>
> Oh I knew full well who he has when I started into it. I did learn a
> couple things though, #1 the use of said device as brute force
> feedback prevention


** Then you learnt nothing - frequency shifters are an elegant form of
feedback reduction since there is no tampering with the PA system's sound
quality or loss of intelligibility.

Eqs are the brute force way.


#2 he hasn't changed a bit!


** Time for you to get real - which will no happen listening to idiots
like Kurt.



............ Phil
Anonymous
October 18, 2004 7:10:27 AM

Archived from groups: rec.audio.pro,r (More info?)

> >** I just told you dickhead

That's an exciting form of verbal masturbation.

> > - a dedicated 5 Hz shifter of high quality
> >for PA system use.

Only an idiot could possibly put all those concepts together in one
sentence including "high quality". Only the sound itself was killed in
this thoughtless experiment.

--
ha
October 18, 2004 11:55:05 AM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

"Phil Allison" <philallison@tpg.com.au> wrote in message news:<2tfgt2F1uetuuU1@uni-berlin.de>...
> "Gary"
> > Kurt Riemann
> >
> >>
> >> You never have to apologize because of anything Phil says.
> >
> > Oh I knew full well who he has when I started into it. I did learn a
> > couple things though, #1 the use of said device as brute force
> > feedback prevention
>
>
> ** Then you learnt nothing - frequency shifters are an elegant form of
> feedback reduction since there is no tampering with the PA system's sound
> quality or loss of intelligibility.
>
> Eqs are the brute force way.

Clearly "brute force" or "elegant" are merely value judgements. I
consider it brute force because you slam your signal through and
you're done. Require any sophistication on the part of the operator?
No. Why are these no longer commonly available for this purpose (at
least in the catalogs I read for audio gear)?
Anonymous
October 18, 2004 1:32:30 PM

Archived from groups: rec.audio.pro,rec.music.makers.synth (More info?)

On 18 Oct 2004 07:55:05 -0700, midicad2001@yahoo.com (Gary) wrote:

>Clearly "brute force" or "elegant" are merely value judgements. I
>consider it brute force because you slam your signal through and
>you're done. Require any sophistication on the part of the operator?
>No. Why are these no longer commonly available for this purpose (at
>least in the catalogs I read for audio gear)?

Because the simply wreck the harmonic structure of the signal. They
were a nice idea in theory, but the results of their use are quite
audible - in a way that the human ear has never had to deal with in
any other natural acoustic phenomena.


Kurt Riemann

check out the examples
http://www.surrealstudios.com/freq-out
!