In the late 60's I remember playing around with a British system that
produced a third channel from a normal stereo record. This back channel
created the ambience of the hall from the differences between the left
and right channels. It was very simple to hook up. All you did was hook
up the new speaker to the positive leads of the left and right
speakers. The record had to have been recorded in a hall to recover the
ambience: records made on mixer boards had no ambience or echo. A
separate amplifier was needed to get the full effect. Some of the
boffins of the time did the math but I don't recall it now. I do recall
getting the effect on Sgt Pepper...good times.

"ve3..." wrote:

In the late 60's I remember playing around with a British system that
produced a third channel from a normal stereo record. This back channel
created the ambience of the hall from the differences between the left
and right channels. It was very simple to hook up. All you did was hook
up the new speaker to the positive leads of the left and right
speakers. The record had to have been recorded in a hall to recover the
ambience: records made on mixer boards had no ambience or echo. A
separate amplifier was needed to get the full effect. Some of the
boffins of the time did the math but I don't recall it now. I do recall
getting the effect on Sgt Pepper...good times.

I remember doing that as well, and it produced an interesting sound.

dxAce
Michigan
USA

Drake R7, R8, R8A and R8B

I swear by, not at, Drake receivers©

"Les Hemmings" wrote:

Eric F. Richards wrote:
Bob Miller wrote:

On Sun, 15 Oct 2006 20:47:00 -0400, SR wrote:

I am interested in learning more about Quadraphonic stereos and
it's music.
I seem to recall quadraphonic LPs came and went in a year or two in
the Seventies. No one could figure out what to put in the rear
speakers. It didn't make sense to be sitting in the middle of a band,
sound-wise.



Mike Oldfield's "Boxed" was produced in quad.. It sounded fine on my
stereo but i was itching to try it out on a proper quad system! Did i miss
much?

Les

I don't know. I never had unrestricted access to a quad system. what
I did -- and this works only on some systems and may be downright
unsafe on others -- was to set up a Hafler Matrix. This is a passive
arrangement of the rear speakers to pull out L-R and R-L information
for back speakers, just wiring them to an existing stereo.

Being a passive system, there isn't a lot of control on what you can
do with it, but it will pull out the surround/quad information in the
right environment.

To wire a Hafler Matrix, you need a system with a common ground for
the left and right channels. Since this isn't a graphic interface,
I'll draw out the wiring on a couple lines:

Left + on stereo ---- Red on Left/Rear speaker
Black on Left/Rear speaker ---- Black on Right/Rear speaker
Red on Right/Rear speaker ---- Right + on stereo

The speakers face each other and should be several feet back from the
listener to introduce a little bit of delay. The arrangement takes
some fiddling to get right, but works on the cheap.

FWIW, the Wikipedia article on Quad elsewhere in this thread claims
that the Hafler Matrix works as well as any other quad/surround method
for pulling the surround info out. I find that *extremely* hard to
believe. But it is a cheap, workable solution.

Regards,


--
Eric F. Richards

"Nature abhors a vacuum tube." -- Myron Glass,
often attributed to J. R. Pierce, Bell Labs, c. 1940

i still have some old quad equipment around here. i played around with
it as a youngster and it got me interested in psycho acoustics. this is
the study of how people hear and perceive sounds and the relationship
between hearing and perceiving sound. it turns out that four discreet
channels are no better than an ambience recovery set-up like hafler or
dolby. this is because we only have two ears so direction is determined
by the time lag between sounds registered in opposite ears. the ears (or
rather the brain) is easily fooled by an artificial sound field like
dolby surround sound. the different channels need not be discreet and it
is easier to process and record using encoding or phase cancelling and
recovery techniques. it all can be done with stereo signals and various
schemes like ambience recovery channels or even simple acoustic reflex
tuning of a hall (this gives a surround sound effect from a simple
stereo signal using only the echoes bouncing back from the walls or
baffles in the playback hall) in short quad died because it was
complicated, redundant and a resource wasting format. a equal effect was
obtained easier with the systems in use today. so why did i keep my
quad stuff? maybe as a reminder of my foolish youth.

James Gabbert of KIOI (K-101) in San Francisco and returned to Lake
Oswego very excited. K-101 had successfully transmitted true
four-channel audio for the first time on a single FM station using
Quadraplex, a process invented by Lou Dorren. The FCC was concerned,
however, with certain technical issues that had to be resolved before
it would give Quadraplex its blessing.
http://www.rockininquad.com/joel%20m...20memories.htm

Quadraphonic Discography "Radio Broadcasts"
http://members.cox.net/surround/quaddisc/quadradi.htm

qua-dra-phonically the sound - echoes all around the inside of my head
~ RHF

I have a modern Casio Keyboard that can play many different pipe organ
sounds.

The Casio Keyboard has build in reflex speakers. Knowing how real pipe
organs works, I was amazed on all of the different parts those speakers
were able to produce at the same time. With depth and separation.

It's almost like a 3D audio experience. -If you will!

We had this crude technology for a very long time. Considering the
history of the organ pipes. The human ear had always been conscience of
the direction of sound.

But unfortunately, I think that many recording studio were either very
expensive to record or not equipped with this type of equipment when
Quadraphonic came out.

Most of pop/rock/rock&roll is usually a piece of music that is usually
less then 4 min long and most of the instruments are playing at the same
time. So a Quadraphonic recording of that might not have much of an effect.

Whereas, with Jazz or Classical music, the pieces are much longer. The
different musical instruments will have individual parts to play and the
many different combinations. Music of these types would be far better
for Quadraphonic recording.

I guess if Quadraphonic technology came out 50 years earlier, it might
of caught on better during the swing/bebop era.

Funny that 3D photography is about 100 year old if not more!

73----73----73---- 73----

Steven



SR wrote:

I am interested in learning more about Quadraphonic stereos and it's music.

Stereos usually had 2 speakers.

But if the stereo had four speakers or more, did that makes it
Quadraphonic?

To know if the stereo was Quadraphonic, must the word Quadraphonic be
mention in the manual? -Describing it as a Quadraphonic Receiver?

And what about Quadraphonic music being broadcast from the radio? How
did that worked?

Does Joe Franklyn, Danny Styles, Symphony Sid or Phil Shapp plays any of
this?

Ah those beautiful stereos with silver faces, needle light and silky
turner. Those were the days!


QTH New York City
73, SR!

On Oct 17, 7:15 am, David wrote:
On 17 Oct 2006 01:45:08 -0700, "RHF"
wrote:

James Gabbert of KIOI (K-101) in San Francisco and returned to Lake
Oswego very excited. K-101 had successfully transmitted true
four-channel audio for the first time on a single FM station using
Quadraplex, a process invented by Lou Dorren. The FCC was concerned,
however, with certain technical issues that had to be resolved before
it would give Quadraplex its blessing.
http://www.rockininquad.com/joel%20m...20memories.htm

Quadraphonic Discography "Radio Broadcasts"
http://members.cox.net/surround/quaddisc/quadradi.htm

qua-dra-phonically the sound - echoes all around the inside of my head
~ RHF
.
.Doesn't he have his own jet airliner?

David - "JG" has had many toys over the years. ~ RHF
http://www.sausalitoartfestival.org/...ssrelease.html

# 56. INVADER · L: 163'7" Y: 1999
http://www.powerandmotoryacht.com/me...00/index6.aspx

* James Gabbert - KIOI (K-101) - SF Bay Area
http://en.wikipedia.org/wiki/KIOI
http://www.bayarearadio.org/audio/kp...959-1960.shtml

* James Gabbert - KTZO Television 20 / KOFY-TV - SF Bay Area
http://en.wikipedia.org/wiki/KBWB
http://www.radiothrills.com/kofy.htm

.
.
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