Natural Science Forum / Physics / Acoustics / June 2004

I am working on the design of a HVAC system which will contain Reheat
Coils within the final ductwork runouts onto each of the floors. The
roomside design is calling for NR 25 - 30 in various spaces. The coils
will be within 1000 mm of the first grille. As such does anyone have

[Cross posted from forum.studiotips.com]
In Cox and D'Antonio's new book on absorbers and diffusers, chapter 1 is
an introduction to the methods used for calculating the absorption
values of porous absorbers.

I'm a biologist, with no background in music and limited physics, so excuse
me if this is a stupid question. Why are there 7 discrete notes? The pitch
we hear is a function of frequency, which is a continuous, not discrete
quantity. So, at first I thought it was kind of like light ...

Entries are requested for Norris prizes, value $1000 per prizewinner,
awarded to composers of music featuring the Seraph piano as described
in the links below:
http://www.google.com/groups?as_umsgid=d3d647a9.0406082151.74b3c7e4@posting.goog
le.com

Folks,
I have a question about acoustics terminology, and I'm hoping the pro
acousticians here will comment.
I have seen some acoustics people use the words Mode and Standing Wave

Prizes, value $1000 per prizewinner, are to be awarded to composers of
music featuring the Seraph piano as described in the links below:
http://www.google.com/groups?as_umsgid=d3d647a9.0406082151.74b3c7e4@posting.goog
le.com
http://www.google.com/groups?as_umsgid=20040422192417.24625 ...

Can anyone point us at a reference(s) or website that deals with sound
propagation in soil and/or rock?
We are trying to get a rough idea of how much attenuation we can expect if
we place noise sources below ground and isolate them with soil versus

Maybe someone can help answer a few questions for me.
A few years ago I had a little ultrasonic transducer that was
about an inch or less in diameter and made out of an aluminum can
with a thinner aluminum face. Unlike current transducers that has

Recently there was a discussion on rec.music.classical.guitar
concerning whether the speed of a finger stroke by itself has any
influence on dynamics. During this discussion, I tried to find
literature that directly answers this question. Surprisingly, I found

This works, I turned several lead atoms into iron atoms, of course I'm
trying to turn them into gold or platinum.
Super-high frequencies will destroy atoms and annoy all the cats and
dogs around.

What is this unit used for and how is it measured?
Stan

Here's one for the gang:
All other things being equal, how much louder (or quieter) would a
given acoustic source be in an atmosphere of pure hydrogen? This is
not as strange a question as it might seem. My current work deals with

I recently submitted a paper which attempted to show a gravity/acoustical
relationship. I really think there might be something to this.
The physicists I have shown this to just look at me with a kind of a "you're
nuts" expression on their faces (actually, one solar

Does anyone know where I might find TL test data for drywall with lead
backing?  I've tried the few manufacturers I could find but none of them
  know if any acoustic testing was ever done.
Thanks much.