RE: Octophonic sound system

["Bailey, Jim" <JBailey@corporate.southam.ca>]

I thought I had posted this to the list before, but perhaps it was to
another one (the topic has come up on three different lists I'm subscribed
to in the last month!). Folks interested in this topic may want to check 
out
the following site:

http://www.york.ac.uk/inst/mustech/3d_audio/ambison.htm

Apologies if it was posted before, but it didn't seem to generate any
response if it was.

Also;

> -----Original Message-----
> From: Stephen P. Goodman [mailto:spgoodman@earthlight.net]
> Sent: Thursday, July 12, 2001 3:16 AM
> To: Loopers-Delight@loopers-delight.com
> Subject: Re: Octophonic sound system
> 
> Have you ever investigated the idea of 
> three-channel?
> Brian Eno put the setup for such a thing in the liner notes 
> for "On Land",
> which alas are in storage with my vinyl in LA - but 
> essentially it's such
> that you have a single speaker that's lower-impedance than 
> your pair of
> other speakers, connected up so that one terminal is on the 
> Left -, and the
> other on Right +.  What one gets out of that speaker is a "subtracted"
> sound, as he put it.  In combination with two speakers however, this
> produces a more "3D" result.

I'm not sure if it's a problem with your nomenclature, Stephen, or a fault
of memory (often my failing). The single speaker should actually be
connected to the +, red, or whatever designation is given to the "hot"
terminal, of _both_ channels. Connecting one side to the -, or black
terminal will just put another load in parallel with whichever + it is
connected to. The purpose is to get a signal going through the third 
speaker
which is NOT common to both sides, which can only be achieved by using the
+es. I've been using this set-up since I first bought "On Land" and it is
amazing. Something I particularly like listening to, in total darkness for
maximum effect, is the beginning of "The Ancients" from "Tales From
Topographic Oceans" by Yes (side three to us vinyl junkies). I also have a
little box made by Dynaco that probably does the same sort of thing, except
that it uses a resistor pad to split the "rear" signal into two channels.
Haven't had the opportunity to set that one up for a long time though.

I'd recommend the set-up to anyone.

Jim Bailey