Natural Science Forum / Physics / Acoustics / December 2006

We need to do field measurements of door TL .
How does one do this?
Do I go according to the known standards for measuring TL of
partitions/walls, and then calculate the relative surfaces of the door

What is Circular motion ??
The direction of a body's motion is constantly changing when it
moves in a circle at a steady speed.
http://www.studyandjobs.com/circular-motion.html

There has been quite a bit of media interest in a University of Michigan
study by a Dr. Kileny, on the sound levels from children's toys.  The source
of the newspaper reports seems to be a press release:
http://www.med.umich.edu/opm/newspage/2006/hmtoys.htm

Does anyone know where I can buy a frequency (in the GHz range) and
amplitude adjustable ultrasound generator? Or else the best or cheapest
way to make one out of readily available parts? Something that can
transmit the sound waves through an aquaeous medium to a biological

After performing an acoustical measurement using a standard tapping
machine as prescribed by ASTM E 1007 on a hardwood floor, we noticed
small marks which are about 1mm wide and 1 mm deep which were left on
the floor after the measurement completed.  I never heard of any

Does anyone have any data on the absorption coefficients for the old
sprayed asbestos acoustical treatments.  We have a temple with 1/2" of
coarse textured treatment on the walls and ceiling over 5/8" gyp.  I
have been figuring that it is similar to 1/2" Sona-spray in acoustical

Article I saw just yesterday:
                Acoustic noise contains valuable information
  December 08, 2006 - The proper processing of acoustic noise can
  provide a wealth of information. Geophysicists have used seismic

Anyone ever experienced what appears to be much (and loud) thermal
noise from polyiso nail base panels? We are involved in a
recently-completed office bldg in St. Louis. The sloped part of the
roof system is comprised of acoustical `F' deck attached via puddle

The interior design world is getting interested in speech privacy
between offices, and at the same time is in love with 5/8" drywall,
which leads to the villain, the 2 kHz coincidence dip.
Decades ago this was fixed with "1# lead" (1mm thick lead foil), but

I need to carry out an octave band analysis but the noise meter I am
using is quite old so does not have the facility to do this
automatically. I'm trying to establish the current noise environment at
a particular site which is to be developed as an industrial facility.

Acoustic Folks
I live in the UK near a main road which is currently being considered for
upgrade to dual carriageway.
We suffer from fairly serious road noise at present, even after we

Gas pressure Calculation
initial pressure x initial volume = final pressure x final volume
http://www.studyandjobs.com/gas-pressure.html
Or learner of physics may visit the link:

I  have an appliance I am trying to quiet, it's an air filter.  It
pushes air through a HEPA filter media and out in to the room.  The max
db rating is only about 85 on it's highest setting but I'd like to see
if it's possible to bring that down.