Suppose I get hold of a recorder that records true level without compressing it,
does anybody here know of a shareware program to take the sound from the sound card input
and display it on the screen as a frequency spectrum?

There's many Web sites where you can find what you want. For example
http://filedudes.ionsys.com/win95/audioap/ has about 90 audio apps, some
of them free, some of them shareware. Many of them include spectrum
analysis. I haven't tried any of them out.

It may be easier/better to first record the sound from the microphone to
a .WAV (don't save as .MP3 since this format has lossy compression),
then later perform the spectrum analysis.

I'd be interested in looking at the data and doing a spectrum analysis,
especially of an unmuffled 13B at a few different RPM settings. Maybe
you could get some recordings, ZIP them up, and post them to the list
(or email them to me if others aren't interested?)

Frank.

Frank, how are we going to get amplitude without a DB meter?
 
Paul Lamar
 
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