Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!rutgers!rochester!pt.cs.cmu.edu!o.gp.cs.cmu.edu!andrew.cmu.edu!jm7e+ From: jm7e+@andrew.cmu.edu (Jeremy G. Mereness) Newsgroups: comp.sys.apple2 Subject: Re: A low blow from Apple Message-ID: Date: 6 Oct 90 19:41:14 GMT References: <0093DC221E311B80.00000110@dcs.simpact.com> Organization: Computing Systems, Carnegie Mellon, Pittsburgh, PA Lines: 37 In-Reply-To: <0093DC221E311B80.00000110@dcs.simpact.com> whitewolf@gnh-starport.cts.com (Tae Song) writes: > |MQUINN@UTCVM.BITNET scribbles... > |>but 4 channel stereo... suround sound. This IBM exec told me this while he > | > Amiga has 4 voice, that's true. BUT it two voice per channel. It's NOT > Surround Sound. Not Quite. Quadraphonic Sound, I guess by definition, would be 4 channel, but 'Surround Sound' is not. Surround Sound is a third, rear channel that is used by the music, television an film industry. It involves incoding the track into the stereo tracks, and then decoding them when the music or whatever is played back. I believe what happens is that you reverse the phase of one of the channels, and then add it to the other channel. Things intended for the rear channel will be recorded slightly out of phase between the front left and right channels, and therefore emphasized in the rear channel if you have one. Normal monophonic recordings cancel out. And, by the way, the rear channel in Surround Sound is monophonic. I know this because my housemates and I built a Surround Sound decoder from an artical in Radio Electronics. Very simple design... and it is amazing just how many recordings employ surround sound. But then again, you start to notice things that don't. But again, Surround Sound is a track that is ENCODED within a normal Stereo Signal. You only need two channels to simulate surround sound, and the encoding is accomplished by judicious use of mixing and phasing. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ |Jeremy Mereness | Support | Ye Olde Disclaimer: | |jm7e+@andrew.cmu.edu (internet) | Free | The above represent my| |a700jm7e@cmccvb (Vax... bitnet) | Software| opinions, alone. | |staff/student@Carnegie Mellon U.| | Ya Gotta Love It. | -----------------------------------------------------------------------