Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!psuvax1!psuvm!auvm!UTCVM!JEFF From: JEFF@UTCVM.BITNET (Jeffrey R Kell) Newsgroups: bit.listserv.emusic-l Subject: Re: PCM follow-up question- Message-ID: <900213.094113.EST.JEFF@UTCVM> Date: 13 Feb 90 14:41:13 GMT Sender: Electronic Music Discussion List Reply-To: Electronic Music Discussion List Organization: University of Tennessee at Chattanooga Lines: 17 Approved: NETNEWS@AUVM Gateway In-Reply-To: Message of Mon, 12 Feb 90 20:18:35 EST from On Mon, 12 Feb 90 20:18:35 EST Kurt A. Geisel said: >How does companding get more dynamic range out of PLAYBACK circuitry >that is only 8-bits wide? By having a seperate overall amplitude >control channel? No, you encode/decode sample values on a non-linear scale, most likely some exponential function. If the A/D D/A conversions are strictly limited to 8-bit you would have to do this on the analog side; for example placing a dBx compander chip set on the analog side of the converters. The magic is the non-linear signal treatment as opposed to simply reducing resolution or padding the signal. ****************************** * If the first person who answers the phone cannot answer your * question, it's a bureaucracy. ******************************