Subject: From: Date:

.WAV clarification Mark Gilmore Thu, 28 Jan 1999 21:12:15 -0800

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I have contributed to confusion regarding "WAVE" file
playback on voice modems: What I SHOULD have said was
PCM/WAVE playback, as "WAVE" files can also be in
"special" formats (such as ADPCM).

So to re-state, I am looking for a modem/utility/method/
libray which will play a PCM/WAVE file thru a voice modem,
OR convert such a file into ROCKWELL/ADPCM WITHOUT the
distortion we are experiencing.

UPDATE/FYI: When I convert a PCM/WAV to ROCKWELL/ADPCM
(using Rockwell's conversion utility), and back again
to a PCM/WAV, the 2nd PCM/WAV plays great (thru SoundBlaster).
SO I KNOW that no data is being lost or corrupted
in the conversion. When I use the Rockwell program
to play the ADPCM file thru the modem, I get the same
distortion as with ECS. So I know that I am not
playing the file "wrong".
OMT: When I convert a high-pitched test-pattern tone
to ADCPM, it plays back ONE OCTAVE lower than the original
(but plays fine if i convert back to pcm).
This can only mean one thing. Perhaps one of you will know
that that one thing is :-).
-- 
Mark Gilmore
Omnipotence (ECS Home Automation Software)
omnip@usit.net
http://www.usit.com/omnip

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