Xref: utzoo comp.sys.mac:15332 unix-pc.general:606
Path: utzoo!mnetor!uunet!ncc!alberta!att-ih!ihnp4!ihlpf!gmark
From: gmark@ihlpf.ATT.COM (Stewart)
Newsgroups: comp.sys.mac,unix-pc.general
Subject: AppleMAC->UNIX-PC VoicePower sounds?
Message-ID: <4517@ihlpf.ATT.COM>
Date: 23 Apr 88 18:53:16 GMT
Organization: AT&T Bell Laboratories - Naperville, Illinois
Lines: 30
Keywords: Conversion,PCM,Formats,audio,sampling rate,INFO & HOW

I am currently trying to convert sounds that a friend has playing
on his Apple Macintosh to the format used by the UNIX-PC (3B1/7300)
VoicePower board.  The Mac has a program to convert the file to
numeric form, and the result SEEMS to be PCM.  The program seems to
allow sampling rates of 11KHz and 22KHz, which I assume is higher
than the sampling rate of the VoicePower board, which seems to be
intended for answering-machine-type applications.  I have written
several programs to translate these files to and from decimal numbers
to binary, remove each Nth sample, scale what I believe is the
amplitude, and had fun but no success in translating.  Anyway, conjecture
aside, what I'm interested in is:

** What are the sound storage formats of the two systems:

	1) PCM, linear or companded, and if so,
	2) what formula?
	3) what "word" size (a byte = an amplitude? 16 bits?)
	4) any header or trailer information in the files that
	   needs to be generated or preserved?
	5) If it turns out that the best way is a direct audio hookup
	   (LEAST desirable, as it is not in the least as much fun)
	   what are the details on the audio I/O jacks on the two machines
	   -- what's necessary?

Any and all help/info./musings appreciated.

					- Mark
					G. Mark Stewart
					ATT-BTL, Naperville, ix1g266
					ixlpq!gms 979-0914