From: dantonio@magick.enet.dec.com (David D'Antonio)
Newsgroups: comp.sys.ibm.pc.soundcard
Subject: Re: GUS Temporal displacement.
Date: 17 Dec 92 19:00:49 GMT
Reply-To: dantonio@flashy.tay2.dec.com
Followup-To: rec.audio
Organization: None to speak of...
Originator: cwatters@top.magnus.acs.ohio-state.edu

In article <1992Dec17.141235.18787@magnus.acs.ohio-state.edu>, cwatters@magnus.acs.ohio-state.edu (Coyt D Watters) writes:
[...]
|>Answering another part of the question:
|>
|>I sell home video/audio/computers, and yes, even the low end CD players can 
|>reproduce temporal displacement, under the right conditions, with a decent,
|>middle of the line stereo system (i.e. not a $149 <10watt tabletop), set
|>up correctly (with the drivers [speakers] located properly).

|>Using a normal listening environment, it's nearly imposssible to distinguish,
|>unless you are sitting in the "sweet spot" where the speakers are able to 
|>create the needed waveform.  A good set of stereo headphones makes a better 
|>environment, although most people can not determine if the sound is located
|>in front or behind them.  I've yet to see a commercial version of a 
|>"surround headphone," though the Virtuality system uses a 4 speaker system
|>in their headset to give front/back information.

I believe that this is what the Carver Sonic Holography box does. It
tries, via signal processing to recreate the effect of listening to a
live performace by selectively canceling the left and right channel
info so that the sound arrives at the correct time to each ear. Given
correct placement of the loudspeakers, it is quite effective. The
clocks in the intro of "Time" from the _Dark Side of the Moon_ album
really are arranged in a row! :-) It also enlarges the "sweet spot". 

|>Unfortunately, the most popular method of producing music is to stick a 
|>microphone up to the instrument/singer or getting a feed from the instrument's
|>amp, then doing the stereo magic at the mixing board.  There have been some
|>items released which were recorded using a "human head microphone", which is
|>a sophisticated system using high-tech materials to create a head with
|>mics in both "ears."  The latest Michael Jackson (no I am NOT a fan) CD has
|>one or two tracks recorded this way.

I've heard of this method as well, but I had also heard that, while
it's quite effective for headphones, room listening suffered. Your
mileage may vary though and I'm not about to run out and buy his album
to test it either. :-)

|>(of course, this has little to do with soundcards, but I figure a lot of 
|> people will be hooking this puppy up to a stereo.  The GUS should be able to
|> do temporal displacement via software, if not hardware.)

I've set the follow-up to rec.audio since it's getting a tad
technical. I'm sure they will be able to expound on this theme
although I'm pretty sure they will instead flame everyone involved for
not have perfectly shielded PCs, soundcard, cables, speakers and ears!
Oh wait, that's rec.audio.high-end...:-)

|>-Coyt 
|>
|>Hey Advanced Gravis! How about a daughterboard which will encode surround sound
|>onto the line out, so an amp with the decoder could give a PC real surround
|>sound?

I'm gonna hook my old Carver Sonic box up and see if it helps!

DDA

--
dantonio@magick.tay2.dec.com -or- dantonio@sword1.enet.dec.com
  I've tried to dance with what life had to hand me
    My partner's been pleasure, my partner's been pain
				-Stevie Nicks