"Chel van Gennip" wrote in message
...

On Thu, 12 Jan 2006 14:09:19 +0100, Arny Krueger wrote:

"Chris Whealy" wrote in message
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For all practical (read audible) purposes, the absorption of sound by
air is not significant for indoor listening situations.

Can you honestly say that after checking the "other references" I
provided above?

A rhetorical question? ;-)

There has been a lot of discussion about "audibility" of the frequencies
above 20 or even 50 kHz. As this verifyable data shows, these frequencies
are absent in a concert hall. I therefore think they should be absent in
recordings too, audible or not.

I find it interesting that the data from Earthworks was only realistic for
rooms where the air was improbably dry.

There seems to be quite a bit of convergence among data from numerous
sources.

It is important to know air does change sound.

It's a low pass filter in real-world applications, plain and simple.

That has implications. If
you do scientific measurements on a violin, you better put the microphone
as close as possible to the instrument, if you want to make a recording
to listen to, keep your distance.

I'm not going to go that far. Close micing is a good way to help manage the
contribution of the room sound to the overall sonic picture. If you have
the luxury of a room that sounds good, then this is less important.

Quite a bit of real-world listening involves being reasonably close to the
players. I still remember the first time I listened to a string quartet
when I could literally reach out and touch their music stands.