In article , Serge Auckland
wrote:
This is a long post, so those not interested can ignore it.

Actually, a very interesting post. Well worth reading. :-)

[snip]

Some time in the sixties, David Hafler proposed a way of extracting
ambience information from two channel stereo, by connecting a third
loudspeaker between the L and R live connections of an amplifier, and
placing this third loudspeaker behind the listener.

[snip]

...but all accepted the commercial need to provide these four channels
from conventional vinyl LPs which could be compatible with non-surround
systems and be broadcastable on mono and stereo radio. At that time,
Reel-to-Reel was not considered acceptable for mass-market programme
distribution - EMI had tried to release stereo recordings on 3 ¾ ips
tape, but with little commercial success in spite of apparently
excellent technical quality. Cassettes were not at the stage of
development that could be called hi-fi,


The article which I happened to read just a few days ago:

"Quadraphonics: What went wrong?" by Adrian Hope Practical HIFi March
1977

Says that when 4 and 8 track recorders started being available in the 1960s
this led to them being used in some cases for 'surround' and that this lead
to both 4-channel reel tapes and 4-channel cartridge tapes being releasefd
for a while in the USA. I can't recall if these ever appeared in the UK.

I assume the industry wanted LP formats for 'compatability' reasons and so
the recordings could be pressed, and avoid the problems/costs of making
tapes.

[snip]


In November 1974's Wireless World, Carey and Sager published proposals
for broadcasting three channel surround, with a fourth being used for
height information, but I have not come across any evidence that their
proposals were acted upon. By then, the public's perception of surround
sound was four loudspeakers arranged in a square or rectangle round the
listener.

Capital Radio (London, UK) did experiment with a 'three channel' system
based on a modification of conventional FM stereo. Alas, it seems they made
a pigs breakfast of the arrangements, and it seemed to then vanish. Didn't
hear it myself, though, so am simply reporting what I've read.

Slainte,

Jim

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