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Making It Loud?
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Bob Cain
science forum Guru


Joined: 07 Jun 2005
Posts: 360

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Doppler Distortion & the "Anonymous Non-believer" Reply with quote

The Ghost wrote:

Quote:

You did nothing meaningful, so there is nothing to refute. As per the
copy/paste of the post below, I am not alone in making that assessment.

Refute the equation I derived or admit you can't.


Bob
--

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

A. Einstein
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The Ghost
science forum Guru Wannabe


Joined: 24 Mar 2005
Posts: 115

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Doppler Distortion & the "Anonymous Non-believer" Reply with quote

Bob Cain <arcane@arcanemethods.com> wrote in
news:ctv9ab0102h@enews1.newsguy.com:

Quote:


The Ghost wrote:


You did nothing meaningful, so there is nothing to refute. As per
the copy/paste of the post below, I am not alone in making that
assessment.

Refute the equation I derived or admit you can't.


Bob


There is nothing to refute. Furthermore you are just as ignorant about what
constitutes a derivation as you are about how to go about solving the
elementary partial differential for one-dimentional wave propagation in a
tube.

Zigoteau did a partial derivation but left you hanging. Thereafter, all
you did was pull equations out of thin air ing anYou
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Brian Ravnaas
science forum beginner


Joined: 24 Mar 2005
Posts: 23

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: wall of water an effective sound barrier? Reply with quote

Dan Jacobson wrote:
Quote:
Just curious if water would be as effective as brick or concrete for
stopping sounds. Heavy and limp. Perhaps a wall of square water
jugs with no gaps.


the mass could be good if it was thick, and the traditional resonance
effects wouldn't be applicable.

however, it would not be appropriate to model this as mass of water
behind jugs having similar performance to similar mass of bricks. Nor
would it be appropriate to model this as having better properties than
the bricks due to the "limp" or not conventionally resonant nature of
the water.

if you wanted to model it, you'd use the normal models, but replace air
in the wall cavity with water. Imagine an infinitely broad sort of
planar "jug". The panels would be the plastic, and the "air" inside
the cavity would be replaced with water.

if you are very curious, i can look through my books and find some
appropriate starting points.
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Brian Ravnaas
science forum beginner


Joined: 24 Mar 2005
Posts: 23

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Reverb room versus ETF Reply with quote

is there any reason to believe that the traditional sets of interacting
equations using in assessing, report, and discussing damping of
mechaniacl resonances would not also be applicable to acoustical
resonances?

for example, the basic relations:

half power bandwidth = the frequency higher than a resonance that is
3dB below peak, minus the frequency lower than the same resonance which
is 3dB below peak

loss factor = half power bandwidth/resonance frequency

decay rate = loss factor * resonance frequency * 27

so via the above, Rt60=2.2/frequency*loss factor where frequency is
the resonance frequency in question


these, save Rt60 perhaps, are applied as a matter of routine to
mechaniacl resonances. Is there any reason they should not also be
applied to room modes?

i am only somewhat familiar with the general calculations intrinsic to
room acoustics, but could one take an FFT at a location that
represented maximum expression of a modal peak, and provided you had a
reliable FFT, utilize the above (or similar, but derived for this
specific purpose) to estimate the damping of the room mode. ?
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Ethan Winer
science forum beginner


Joined: 08 Jun 2005
Posts: 37

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Reverb room versus ETF Reply with quote

Hi Brian,

Thanks. Your comments, here and elsewhere, are all greatly appreciated.

Quote:
i am only somewhat familiar with the general calculations

As you may or may not know, I'm not much of a math guy. So I have to leave
it to people like you and Jeff and the other experts here to determine how
to derive Sabins of absorption from decay. I'm not even sure how to get
decay directly from my tests, since ETF will not output numbers for the
waterfall plots. Maybe one could overlay a labeled 3D grid in a graphics
program to better identify the various points on the graph?

Then there's still the problem of some peaks being hidden behind others. I
have a series of plots I took in the same room at five different locations,
all with the room empty. In some room locations, modes that had been hidden
behind others elsewhere in the room now show clearly, and vice versa. So it
seems to me the next step is to try to convince Doug Plumb (ETF author) to
add the ability to export the 3D data from those plots.

One final point: Even though the peaks change amplitude a lot at the
different places, the relative decay appears to be more or less constant.
That is, modes that decay slowly at one place decay slowly elsewhere too,
and likewise for modes that decay more quickly. So I take that as further
proof that the basic premise of assessing absorption by measuring modal
decay is valid regardless of where the measuring microphone is placed.

--Ethan
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Guest






PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Removing hum from a recording Reply with quote

If the intensity varies slow enough for you to hear it, that would only
affect a handful of frequencies, maybe only 10Hrz around it, not two
kHz (between 15khz and 17khz), and since you are only doing several
hertz you don't need an FFT, so you don't need to brake up the
file, just find out the exact frequency - I believe it is
15k+something - and remove every frequency from five above it to five
below it, everything else you hear may be the animals, Please update.
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The Ghost
science forum Guru Wannabe


Joined: 24 Mar 2005
Posts: 115

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Removing hum from a recording Reply with quote

lemo5@optonline.net wrote in
news:1107984794.307476.101380@o13g2000cwo.googlegroups.com:

Quote:
That's nice, but I fail to see what that has to do with either
removing hum
from a recording, or with your incorrect assertion that this ghost >is
dead.

You wouldn't by chance be an alter ego to Bevis & Butthead of >the
audio
groups?

I have never been haunted before - especially over the internet, it is
quite an interesting experience.


If you believe that you are being haunted, I suggest that you see a shrink.
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The Ghost
science forum Guru Wannabe


Joined: 24 Mar 2005
Posts: 115

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Multi track recording software? Reply with quote

Bob Cain <arcane@arcanemethods.com> wrote in
news:curg3902r1r@enews2.newsguy.com:

Quote:


Porky wrote:

*LOL* Ya think the ghost thinks we've progressed? :-)

The Ghost is an automoton, an Eliza like trolling program
put together by Gary Sokolich, an unemployed acoustics
clerk, between his bouts of compulsive masturbation. It has
a bot function now that stalks me by monitoring, via Google,
all of my usenet postings in any group to interject its venom.

I was really surprised when it showed up the other day in
comp.apl but I guess I shouldn't be surprised at anything
arriving from that direction other than sanity.


Bob


Your previous postings pretty much document the severity and extent of your
mental illness, so the above revelation should be of no surprise to anyone.
Just how long have you been peeping in windows watching middle aged men
masturbate. Have you also been taking pictures and/or videos. They would
certainly be helpful in the event that you need to defend your assertion.
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The Ghost
science forum Guru Wannabe


Joined: 24 Mar 2005
Posts: 115

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: FFT quantization vs. simple DFT Reply with quote

Bob Cain <arcane@arcanemethods.com> wrote in
news:cum4ck02tv4@enews2.newsguy.com:

Quote:

That doesn't seem intuitive to me but error analysis is
obviously not my forte so I can be rather easily persuaded
either way and probably will be a couple of times before
this issue gets resolved. Smile


Error analysis isn't the only thing that isn't your forte. A short list
would read something like this: elementary physics, elementary acoustics,
elementary engineering math.

Anyone interested in getting an education in non-scientific discourse (aka
mindless nonsesical drivel) should study the exchanges between you and the
Bevis & Butthead duo (porky and jim carr) that took place last year in the
audio groups. However, in order to avoid confusion, they need to start
from the beginning because initially, according to you, Doppler distortion
didn't exist under any circumstances. Then, according to you, it existed
in a free field, but not in a tube. Then later, according to you, it
existed in a tube as well, and presumably everywhere else. And, in the
end, you were pulling nonsensical equations and meaningless terminology out
of the orifice where the sun doesn't shine to purportedly prove it.

Aside from the hatred that you harbor toward me, and your four-year
obsession with posting false, defamatory and slanderous comments about me
all over the internet, what exactly is your forte?
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Porky
science forum beginner


Joined: 25 Mar 2005
Posts: 41

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Nested Vectors and Indexing Reply with quote

"John Sullivan" <john@yddraiggoch.demon.co.uk> wrote in message
news:1hze2J4uIuGCFAXF@yddraiggoch.demon.co.uk...
Quote:
Can you two children take this mutual trading of insults to email and
get it out of the newsgroup, please?


Careful, John, the ghost will sic his 'bot on you too. He followed Bob to

alt.music.home-studio and started in on anyone who asked him to stop there
too, and that was months ago. He's harder to get rid of than a bad habit.
Smile
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The Ghost
science forum Guru Wannabe


Joined: 24 Mar 2005
Posts: 115

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Nested Vectors and Indexing Reply with quote

"Porky" <noham@nospam.com> wrote in
news:OaTSd.7080$Q47.3263@bignews5.bellsouth.net:

Quote:

"John Sullivan" <john@yddraiggoch.demon.co.uk> wrote in message
news:1hze2J4uIuGCFAXF@yddraiggoch.demon.co.uk...
Can you two children take this mutual trading of insults to email and
get it out of the newsgroup, please?


Careful, John, the ghost will sic his 'bot on you too. He followed
Bob to
alt.music.home-studio and started in on anyone who asked him to stop
there too, and that was months ago. He's harder to get rid of than a
bad habit.
:-)


Is compulsive lying a recent development or something that has plagued you
your entire life?
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Brian Ravnaas
science forum beginner


Joined: 24 Mar 2005
Posts: 23

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Reverb room versus ETF Reply with quote

life is a busy thing, isn't it?

so many projects get sort of shelved, and then forgotten. i wonder
what the average person who is in an exploratory field has as a list of
should-haves and wish-i-would-haves when they retire?
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Roger Bagula
science forum addict


Joined: 03 May 2005
Posts: 59

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Making It Loud? Reply with quote

Singers use a microphone filter called a b filter which can be obtained
at music stores. I coat hanger with a womans panty hose stretched over
it is what a woman singer
I know uses in recording ( much cheaper!).
Ron Hubbard wrote:

Quote:
Hi, All;

I want to do some experiments with magnetostrictive transducers,
particularly rings. I have the idea to fire a jolt of high voltage from
an electronic flash unit into a ring of Terfenol- D whose resonant
frequency will be about 15 kHz. Does anyone know if some sort of
diaphragm is needed to make the sound pulse audible? And if so, what
would probably
be the best way to go about that?

Any help in this would be deeply appreciated. Thanks.

Ron

--
"You see me now a veteran, of a thousand psychic wars.
I've been living on the edge so long where the winds of limbo roar."






--
Roger L. Bagula email: rlbagula@sbcglobal.net or
rlbagulatftn@yahoo.com
11759 Waterhill Road,
Lakeside, Ca. 92040 telephone: 619-561-0814}
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Ron Hubbard
science forum addict


Joined: 17 May 2005
Posts: 55

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Making It Loud? Reply with quote

"Roger Bagula" <rlbagulatftn@yahoo.com> wrote in message
news:BkD_d.24250$OU1.7788@newssvr21.news.prodigy.com...
Quote:
Singers use a microphone filter called a b filter which can be
obtained
at music stores. I coat hanger with a womans panty hose stretched over
it is what a woman singer
I know uses in recording ( much cheaper!).
Ron Hubbard wrote:

Hmm... I'm trying to make a sonar-like ultrasonic pulser, only
one designed to work in air rather than a medium like water. Once I send
a high voltage pulse through a coil wrapped around a ring of some
material like nickel, cobalt, Terfenol-D, the ring will oscillate,
briefly, at it's resonant frequency converting electricity into sound.
But then the problem becomes how to couple that sound source to the air
for maximum sound transmission.

Ron
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Roger Bagula
science forum addict


Joined: 03 May 2005
Posts: 59

PostPosted: Thu Mar 24, 2005 10:04 pm    Post subject: Re: Making It Loud? Reply with quote

Use a drum :
make the sound hit a drum diaphragm.
( drum diaphragms are nice because you can put particles on them
and detect the harmonic shape of the sound.)
Another alternative is to make it resonant an organ pipe.
It depends on what kind of harmonics you want to set,
doesn't it?
The b filter takes out vortices as I understand it that are set by "b"'s
and "p"'s that mess up microphones by giving popping noises.
I thought you were having troubles getting your sounds recorded
due to turbulance produced by your method.
Ron Hubbard wrote:

Quote:
"Roger Bagula" <rlbagulatftn@yahoo.com> wrote in message
news:BkD_d.24250$OU1.7788@newssvr21.news.prodigy.com...

Singers use a microphone filter called a b filter which can be

obtained

at music stores. I coat hanger with a womans panty hose stretched over
it is what a woman singer
I know uses in recording ( much cheaper!).
Ron Hubbard wrote:


Hmm... I'm trying to make a sonar-like ultrasonic pulser, only
one designed to work in air rather than a medium like water. Once I send
a high voltage pulse through a coil wrapped around a ring of some
material like nickel, cobalt, Terfenol-D, the ring will oscillate,
briefly, at it's resonant frequency converting electricity into sound.
But then the problem becomes how to couple that sound source to the air
for maximum sound transmission.

Ron




--
Roger L. Bagula email: rlbagula@sbcglobal.net or
rlbagulatftn@yahoo.com
11759 Waterhill Road,
Lakeside, Ca. 92040 telephone: 619-561-0814}
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