I have provided direct experimental measurements of dynamic Doppler
shift. I have also provided a reference to the analysis of
instantaneous dynamic Doppler shift that is given in a classical
textbook on Acoustics by a well respected and reputable author. It is
time for Bob Cain and his equally mindless followers to accept reality
and to acknowledge defeat. While the senseless debate over the
existence of dynamic Doppler shift will undoubtedly continue among the
audio illiterates who prefer to deny reality rather than accept
experimental proof and/or who are incapable of understanding the
applicable math, from a purely scientific perspective, the issue is
settled and the debate is over.

The Ghost wrote:

I have provided direct experimental measurements of dynamic Doppler
shift. I have also provided a reference to the analysis of
instantaneous dynamic Doppler shift that is given in a classical
textbook on Acoustics by a well respected and reputable author. It is
time for Bob Cain and his equally mindless followers to accept reality
and to acknowledge defeat. While the senseless debate over the
existence of dynamic Doppler shift will undoubtedly continue among the
audio illiterates who prefer to deny reality rather than accept
experimental proof and/or who are incapable of understanding the
applicable math, from a purely scientific perspective, the issue is
settled and the debate is over.

ROTFLOL!

Your experiment does not separate variables. Try it
sometime. Other than corrupted data are you ever going to
offer anything substantive to this discussion?

Why, if it does, do you think Doppler distortion exists? I
take it from your implicit support that you accept the
vernacular argument. How about a predictive theory that
tells what to expect quantitatively. Start with the piston
in a tube (infinite plane generating a plane wave) and
graduate to a piston in a baffle. It's totally different
depending on the configuration but I suppose you knew that.
Almost none of it occurs in the very near field of the
speaker, but I'm sure you knew that.

Actually, I've come to realize that you are a fraud. If you
knew anything it is certain you'd be spouting it. Perhaps
once you did but it seems to have been eaten by the acid of
your disturbed mind. Or are we supposed to accept your
brilliance based on your nasty attitude and the carping it
produces? You are a legend in your own mind. The reality
of your legend is quite different.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein

"Bob Cain" wrote in message


Your experiment does not separate variables.

But mine does.

Arny Krueger wrote:

"Bob Cain" wrote in message



Your experiment does not separate variables.


But mine does.

Please explain once again for this tired old brain how,
specifically, it does that. I honestly didn't see that in
what you've written.


Thanks,

Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein

"Bob Cain" wrote in message

Arny Krueger wrote:

"Bob Cain" wrote in message



Your experiment does not separate variables.


But mine does.

Please explain once again for this tired old brain how,
specifically, it does that. I honestly didn't see that in
what you've written.

I've written about the fact that the test signal from the microphone was
bandpass filtered and tremendously clipped, thus removing all amplitude
modulation. Sidebands characteristic of FM remained.

Arny Krueger wrote:


Please explain once again for this tired old brain how,
specifically, it does that. I honestly didn't see that in
what you've written.


I've written about the fact that the test signal from the microphone was
bandpass filtered and tremendously clipped, thus removing all amplitude
modulation. Sidebands characteristic of FM remained.

Sorry, Arny. This in no way eliminates the effects of the
mechanical imperfections of the speaker. What would is
optical measurement of its motion compared to the sound it
generates. There are likely other, more accessable ways, to
measure that motion.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein

How about a predictive theory that tells what to
expect quantitatively?

I have repeatedly stated the simple mathematical steps needed to derive a useful
formula. I'm not going to do this for you, Bob. If you don't have the trivial
knowledge or skill to do this for yourself -- then why should you be interested
in the "maths" of Doppler shift in the first place?

It's about time you let the issue drop.

William Sommerwerck wrote:

How about a predictive theory that tells what to
expect quantitatively?


I have repeatedly stated the simple mathematical steps needed to derive a useful
formula. I'm not going to do this for you, Bob.

The fact that you believe it so simple truly tells the
degree to which such a comment is credible from you.

Fact is, you couldn't because you don't understand it at
all. I'm getting closer and do actually have hope that with
some outside assistance a correct mathematical expression
can be produced for some common cases.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein

I have repeatedly stated the simple mathematical steps needed
to derive a useful formula. I'm not going to do this for you, Bob.

The fact that you believe it so simple truly tells the
degree to which such a comment is credible from you.

Fact is, you couldn't because you don't understand it at
all. I'm getting closer and do actually have hope that with
some outside assistance a correct mathematical expression
can be produced for some common cases.

It is precisely because I understand it that I realize how simple it is. Note
your own signature! (Which, by the way, I believe is a misquote.) You are
overanalyzing something that is not complicated.

Any number of people in this group, including Arny, Fletcher, Steve, Ralph,
Waldo, and Emerson, could easily throw together the equations. It's trivial.

Bob, I have no trouble with you thinking you're bright, clever, and insightful.
(Heck, I think _I_ am.) I do object when you think others aren't.

I, too, occasionally raise points that other people just don't seem to "get."
But I BACK OFF after a while, and think about them some more.

William Sommerwerck wrote:

Any number of people in this group, including Arny, Fletcher, Steve, Ralph,
Waldo, and Emerson, could easily throw together the equations. It's trivial.

Then why hasn't anyone? That would give something concrete
to prove or disprove.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein

Bob Cain wrote:



William Sommerwerck wrote:

How about a predictive theory that tells what to
expect quantitatively?



I have repeatedly stated the simple mathematical steps needed to
derive a useful
formula. I'm not going to do this for you, Bob.


The fact that you believe it so simple truly tells the degree to which
such a comment is credible from you.

That wasn't at all fair, Willian, and I appologize. I
started with the standard assumption that you are making
too. What it led to mathematically was an infinite regress
or recursion where a function was defined in terms of
itself. I could find absolutely no way out of this dillema.
While in some similar situations, there is a kind of
convergence in the limit, this did not appear to be one of
them, in fact it predicted classical recursive chaos that is
essentially unpredictable. Numerical simulation also showed
that by producing a spectrum that was nearly white noise.

I didn't believe that because it doesn't sound like that and
I took that as my first evidence beyond simple intuition
that something was wrong with the accepted model.

I invite you to try where I have failed with that model.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein

The fact that you believe it so simple truly tells the
degree to which such a comment is credible from you.

That wasn't at all fair, Willian, and I appologize. I started
with the standard assumption that you are making, too.

That isn't obvious to me, except possibly for the point I make below -- qv.


What it led to mathematically was an infinite regress
or recursion where a function was defined in terms of
itself. I could find absolutely no way out of this dillema.

Not every problem has a simple or closed solution. A good approximation can be
completely satisfactory. That's why we have tables of integrals for functions
that don't have expressable integrals. (Can't think of the right word.)

Remember the scene in "The Day the Earth Stood Still" where the Einstein
character asks Klaatu about the fact the blackboard formula doesn't have an
exact solution? Klaatu replies that the approximation is good enough to get him
from planet to planet.

From my perspective, you're making something complicated out of something
simple. I might be wrong, but it seems very plain to me. Not because I would
like it to be, but because I think this is a fundamentally simple problem with a
fundamentally simple analysis.

Point made below: I believe that my explanation and the "simple" corresponding
math is "correct," with one obvious omission -- it does not model the modulation
of the lower frequency by the upper -- if such an effect exists. Is this what
causes the "infinite regression" in your treatment?

One other point... One of the reasons I'm so fussy and argumentative about this
issue is that, over the years, I've been most-impressed by scientists who give
simple, elegant explanations. (Correct explanations, of course!) I consciously
try to model my explanations accordingly.


While in some similar situations, there is a kind of
convergence in the limit, this did not appear to be one of
them, in fact it predicted classical recursive chaos that is
essentially unpredictable. Numerical simulation also showed
that by producing a spectrum that was nearly white noise.

I didn't believe that because it doesn't sound like that and
I took that as my first evidence beyond simple intuition
that something was wrong with the accepted model.

I invite you to try where I have failed with that model.

"William Sommerwerck" wrote in message
...
How about a predictive theory that tells what to
expect quantitatively?

I have repeatedly stated the simple mathematical steps needed to derive a
useful
formula. I'm not going to do this for you, Bob. If you don't have the
trivial
knowledge or skill to do this for yourself -- then why should you be
interested
in the "maths" of Doppler shift in the first place?

It's about time you let the issue drop.


I can't tell from whence William posts, so I'll continue the cross-posting.

With all due respect, your assertion that this is simple math is simply not
true. Taking the basic Doppler formula and making it into a time-variant
formula requires knowledge of calculus, and the average Joe (no reflection
upon Bob intended) does not consider calculus simple. Instead of repeatedly
berating Bob for failing to grasp the seemingly obvious, why don't you post
the formula for all to see?

--
Michael Ellis
first initial last name at pesa commercial account

With all due respect, your assertion that this is simple math is simply not
true. Taking the basic Doppler formula and making it into a time-variant
formula requires knowledge of calculus, and the average Joe (no reflection
upon Bob intended) does not consider calculus simple. Instead of repeatedly
berating Bob for failing to grasp the seemingly obvious, why don't you post
the formula for all to see?

What is so complicated about plugging the velocity of the cone into the Doppler
formula?

You then have an expression in which the frequency shift varies as the sine of
the frequency moving the cone -- in other words, a carrier (the high frequency)
FM-modulated by the cone displacement-frequency.

Once you've figured out the modulation index, you can look up the sideband
amplitudes from a table of Bessel functions.

This is trivial stuff, guys.

"William Sommerwerck" wrote in message
...
With all due respect, your assertion that this is simple math is simply
not
true. Taking the basic Doppler formula and making it into a time-variant
formula requires knowledge of calculus, and the average Joe (no
reflection
upon Bob intended) does not consider calculus simple. Instead of
repeatedly
berating Bob for failing to grasp the seemingly obvious, why don't you
post
the formula for all to see?

What is so complicated about plugging the velocity of the cone into the
Doppler
formula?

You then have an expression in which the frequency shift varies as the
sine of
the frequency moving the cone -- in other words, a carrier (the high
frequency)
FM-modulated by the cone displacement-frequency.

Once you've figured out the modulation index, you can look up the sideband
amplitudes from a table of Bessel functions.

You, sir, seem to have made my point.

This is trivial stuff, guys.

Validation by repetition?

--
Michael Ellis
first initial last name at pesa commercial account

William Sommerwerck wrote:

What is so complicated about plugging the velocity of the cone into the Doppler
formula?

You then have an expression in which the frequency shift varies as the sine of
the frequency moving the cone -- in other words, a carrier (the high frequency)
FM-modulated by the cone displacement-frequency.

Once you've figured out the modulation index, you can look up the sideband
amplitudes from a table of Bessel functions.

This is trivial stuff, guys.

Then why don't you just do it? I simply don't get this
argument of yours when you refuse to do anything about
backing it up despite its simplicity. I told you that I
tried and failed to get anything meaningful. If it so easy,
please show me how.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein

What is so complicated about plugging the velocity of the cone into the Doppler
formula?

You then have an expression in which the frequency shift varies as the sine of
the frequency moving the cone -- in other words, a carrier (the high frequency)
FM-modulated by the cone displacement-frequency.

Once you've figured out the modulation index, you can look up the sideband
amplitudes from a table of Bessel functions.

This is trivial stuff, guys.

I have already done this in a previous posting and the results agreed
with what was seen on the spectrum analyzer.

Mark

Michael W. Ellis wrote:

"William Sommerwerck" wrote in message
...
I can't tell from whence William posts, so I'll continue the cross-posting.

P L E A S E S T O P C R O S S - P O S T I N G TO

ALT....ACOUSTICS.

W E D O N O T N E E D T H I S. ! ! ! ! !

Have a good day,

Angelo Campanella

Angelo Campanella wrote:

Michael W. Ellis wrote:

"William Sommerwerck" wrote in message
...
I can't tell from whence William posts, so I'll continue the
cross-posting.


P L E A S E S T O P C R O S S - P O S T I N G TO

ALT....ACOUSTICS.

W E D O N O T N E E D T H I S. ! ! ! ! !

If it doesn't interest you, kill the thread.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein

On Fri, 20 Aug 2004 00:36:23 -0700, Bob Cain
wrote:

...stuff deleted....

Why, if it does, do you think Doppler distortion exists? I
take it from your implicit support that you accept the
vernacular argument. How about a predictive theory that
tells what to expect quantitatively. Start with the piston
in a tube (infinite plane generating a plane wave) and
graduate to a piston in a baffle. It's totally different
depending on the configuration but I suppose you knew that.
Almost none of it occurs in the very near field of the
speaker, but I'm sure you knew that.


I just waded through "Theoretical Acoustics", Morse and
Ingard,1968,pp698-737. The apparent recieved frequency shift from a
moving monopole, dipole, plane wave source (piston cylinder), are all
the same, if you are 90 degrees to the source. The frequency shift
(subsonic case) all follows the simple case. This is a relativity
issue..... we're dealing with two coordinate systems that are moving
relative to each other.
Distortion is not an issue here, just frequency shift.
w1=w0/(1-M) where w1 is apparent freq.
w0 is freq from moving source
M is v/c where v is velocity of source, c is speed
of sound
Distortion is a whole other ball game, depending on velocity profile
with respect to time and the frequency shift from the above equations.

I have tried to follow the various arguments, but I have difficulty
making sense out of most of them. In most cases "you're both right",
but arguing from very different perspectives, or someone is focussing
on a very narrow line of reasoning, different from his "rival". I
hated even to get into this argument because of the mudslinging from
frustrated "players".
Doppler shift is real.... try it! In order to hear it readily, you
need a low freq. source 1-100Hz (the brain can't easily detect other
modulating freq. ... around 60 Hz is best), and a 1000 Hz signal. The
low freq. will have to be very stong, a hefty woofer (long throw) will
do. The lower freq. will enable you to hear the shifting frequencies,
and thus discriminate against AM modulation. From my experience, high
modulation index (M)is the most audible, M=(freq shift)/(modulating
freq). M should be larger than 0.5 to be readily noticed.

-Paul
.................................................. .............
Paul Guy
Somewhere in the Nova Scotia fog

Bob Cain wrote in message ...
The Ghost wrote:

I have provided direct experimental measurements of dynamic Doppler
shift. I have also provided a reference to the analysis of
instantaneous dynamic Doppler shift that is given in a classical
textbook on Acoustics by a well respected and reputable author. It is
time for Bob Cain and his equally mindless followers to accept reality
and to acknowledge defeat. While the senseless debate over the
existence of dynamic Doppler shift will undoubtedly continue among the
audio illiterates who prefer to deny reality rather than accept
experimental proof and/or who are incapable of understanding the
applicable math, from a purely scientific perspective, the issue is
settled and the debate is over.

ROTFLOL!

Your experiment does not separate variables. Try it
sometime. Other than corrupted data are you ever going to
offer anything substantive to this discussion?

Why, if it does, do you think Doppler distortion exists? I
take it from your implicit support that you accept the
vernacular argument. How about a predictive theory that
tells what to expect quantitatively. Start with the piston
in a tube (infinite plane generating a plane wave) and
graduate to a piston in a baffle. It's totally different
depending on the configuration but I suppose you knew that.
Almost none of it occurs in the very near field of the
speaker, but I'm sure you knew that.

Actually, I've come to realize that you are a fraud. If you
knew anything it is certain you'd be spouting it. Perhaps
once you did but it seems to have been eaten by the acid of
your disturbed mind. Or are we supposed to accept your
brilliance based on your nasty attitude and the carping it
produces? You are a legend in your own mind. The reality
of your legend is quite different.

There are many people who pay me handsomely for my knowledge,
experience and technical ability, and it is their opinions, not yours,
that are important and that matter. If you are unable to recognize
and appreciate the validity and value of the information that I have
provided, that is your problem, not mine. I have gone out and caught
the food, prepared the meal and put it on the table in front of you.
If you expect me to spoon feed the meal to you, that isn't going to
happen. With regard to your most recent ad hominem attack, it is not
something that is either new or unexpected. Such ad hominem attacks
directed at me in alt.sci.physics.acoustics have been a trademark of
yours for the past three or four years. However, your most recent ad
hominem attacks in the audio groups have been much more vitriolic than
those in the past. No doubt that is because I have come onto your
turf where you are on center stage and all of your audio buddies are
watching, and because you are loosing the debate.

The Ghost wrote:

If you are unable to recognize
and appreciate the validity and value of the information that I have
provided, that is your problem, not mine.

You have offered no such information; zip, nada, nothing.
You have only postured as you are continuing to do in the
post I'm referencing. Ad hominem is exactly right. You
deserve no more.


Bob
--

"Things should be described as simply as possible, but no
simpler."

A. Einstein

"The Ghost" wrote in message
om...
Bob Cain wrote in message
...
The Ghost wrote:

I have provided direct experimental measurements of dynamic Doppler
shift. I have also provided a reference to the analysis of
instantaneous dynamic Doppler shift that is given in a classical
textbook on Acoustics by a well respected and reputable author. It is
time for Bob Cain and his equally mindless followers to accept reality
and to acknowledge defeat. While the senseless debate over the
existence of dynamic Doppler shift will undoubtedly continue among the
audio illiterates who prefer to deny reality rather than accept
experimental proof and/or who are incapable of understanding the
applicable math, from a purely scientific perspective, the issue is
settled and the debate is over.

ROTFLOL!

Your experiment does not separate variables. Try it
sometime. Other than corrupted data are you ever going to
offer anything substantive to this discussion?

Why, if it does, do you think Doppler distortion exists? I
take it from your implicit support that you accept the
vernacular argument. How about a predictive theory that
tells what to expect quantitatively. Start with the piston
in a tube (infinite plane generating a plane wave) and
graduate to a piston in a baffle. It's totally different
depending on the configuration but I suppose you knew that.
Almost none of it occurs in the very near field of the
speaker, but I'm sure you knew that.

Actually, I've come to realize that you are a fraud. If you
knew anything it is certain you'd be spouting it. Perhaps
once you did but it seems to have been eaten by the acid of
your disturbed mind. Or are we supposed to accept your
brilliance based on your nasty attitude and the carping it
produces? You are a legend in your own mind. The reality
of your legend is quite different.

There are many people who pay me handsomely for my knowledge,
experience and technical ability, and it is their opinions, not yours,
that are important and that matter. If you are unable to recognize
and appreciate the validity and value of the information that I have
provided, that is your problem, not mine. I have gone out and caught
the food, prepared the meal and put it on the table in front of you.
If you expect me to spoon feed the meal to you, that isn't going to
happen.

You know, you seem to say that to a lot of people as if you've never heard
the expression, "Put up or shut up."
Why don't you try that sometime; I'm sure it'll be a novel experience for
you.

-rh

On Sat, 21 Aug 2004 04:26:53 -0700, "Ron Hubbard"
wrote:

You know, you seem to say that to a lot of people as if you've never heard
the expression, "Put up or shut up."
Why don't you try that sometime; I'm sure it'll be a novel experience for
you.

Seems to me that Gary has "put up" plenty of times. Even on this
topic, he's taken the time to perform an experiment and report the
results. I think his posts have come within a hair of handing
everyone the answer on a silver platter.

Of course, there are a few participants who understand the subject and
don't need anything handed to them. Versus those who would rather
discuss it at the level of 12 year olds applying relativity to explain
Star Trek plot twists, and wouldn't know what to do with a silver
platter anyway.

Ken Plotkin

"Ken Plotkin" wrote in message
...
On Sat, 21 Aug 2004 04:26:53 -0700, "Ron Hubbard"
wrote:

You know, you seem to say that to a lot of people as if you've never heard
the expression, "Put up or shut up."
Why don't you try that sometime; I'm sure it'll be a novel experience for
you.

Seems to me that Gary has "put up" plenty of times. Even on this
topic, he's taken the time to perform an experiment and report the
results. I think his posts have come within a hair of handing
everyone the answer on a silver platter.

The OP experiment (a high-frequency radiator mounted on a low-frequency,
non-radiating platform) are not the same conditions as a loudspeaker (a
high-frequency radiator mounted on a low-frequency, *radiating* platform).
You can't separate the two. It's not a silver platter, it's a red herring.

To simplify the problem, try the experiment with just one frequency. The
Doppler shift, if is occurring, should distort a single-frequency waveform
by compressing the slope as the piston moves forward, and stretching the
slope as the piston moves backward. But we know that this does not happen
until the motion is so extreme that the air in front of the piston becomes
inelastic.

"Ron Hubbard" wrote in message ...

You know, you seem to say that to a lot of people as if you've never heard
the expression, "Put up or shut up."
Why don't you try that sometime; I'm sure it'll be a novel experience for
you.

A truly thoughtful and brilliant assessment, Ron. Take another drink
and go to sleep. When you wake up, take a bath, and put on some
clothes and have a meal consisting of solid food for a change. Then
put that bathrobe that you have been wearing for several months
straight, while watching all those soaps, into the wash. If you don't
have a washing machine, then at least soak it in the toilet for a few
hours before you put it back on. Then, before you hit the bottle
again, and while you are still partially lucid, read the thread which
I initiated entitled "Experimental Evidence for Dynamic Doppler
Shift." Finally, since everyone already knows that you have nothing
to "put up" I suggest that you follow your own advice and just "shut
up."