Quadraphonic PINK FLOYD Dark Side of the Moon
 

Title lifted from an Ebay auction with Pink Floyd
search terms.

I've read a little about quad LPs recently. If my understanding
is correct, the encoding is a little like FM stereo in that there
is information encoded in HF above the audible range, and it's
something to do with sum-and-difference, that when decoded,
yields the rear channel information. How close am I?

I was surprised when I read that, since I assume a lot of that
information is above 20kHz, and quad was en vogue back in the 70s.
Were cartridges and preamps of the time capable of picking up signals
way in excess of 20kHz accurately?

Let's suppose I were to buy a Floyd DSOTM quad LP from Ebay:
Is there any equipment now that could take the output from
my cartridge and decode it? (Kinda irrelevant in fact because
I only have 2 speakers and a stereo amp, but... In the bottom of
my heart...) I would imagine that you can't easily get that kind
of gear any more.

Also, since the groove modulation extends to much higher frequencies
than it does with normal stereo, would playing it with a normal
cartridge/stylus be likely to cause it great (brain) damage (I use a
Sumiko Blue Point Special Evo III)?

How different was the back-channel information from the main
front signal? Could you, in practice, have 4 completely
different signals (vocals, for example) coming from the 4
speakers with very little crosstalk? Would the strident
tintinnabulation starting "Time" be different from each corner?

Yours, not-old-enoughly-but-very-nearly,


Martin

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Fleetie" wrote in message
...
Title lifted from an Ebay auction with Pink Floyd
search terms.

I've read a little about quad LPs recently. If my understanding
is correct, the encoding is a little like FM stereo in that there
is information encoded in HF above the audible range, and it's
something to do with sum-and-difference, that when decoded, yields the
rear channel information. How close am I?


I was surprised when I read that, since I assume a lot of that
information is above 20kHz, and quad was en vogue back in the 70s.
Were cartridges and preamps of the time capable of picking up signals
way in excess of 20kHz accurately?

Let's suppose I were to buy a Floyd DSOTM quad LP from Ebay:
Is there any equipment now that could take the output from
my cartridge and decode it? (Kinda irrelevant in fact because
I only have 2 speakers and a stereo amp, but... In the bottom of
my heart...) I would imagine that you can't easily get that kind
of gear any more.

Also, since the groove modulation extends to much higher frequencies
than it does with normal stereo, would playing it with a normal
cartridge/stylus be likely to cause it great (brain) damage (I use a
Sumiko Blue Point Special Evo III)?

How different was the back-channel information from the main
front signal? Could you, in practice, have 4 completely
different signals (vocals, for example) coming from the 4
speakers with very little crosstalk? Would the strident
tintinnabulation starting "Time" be different from each corner?

Yours, not-old-enoughly-but-very-nearly,


Martin

There were three basic encoding methods for quad records in the 70s. SQ and
QS were matrixed systems which means that the rear channels were encoded
essentially by phase differences in with the front channels. This would make
it reasonably compatible with normal stereo and almost compatible with mono,
important for broadcasting which was mostly on AM in those days.

The third encoding method, which you allude to in your post was CD4, which
was a carrier system similar to FM in that the front plus rear channels were
mixed in the base-band, and the front-rear encoded on a carrier and then
decoded on playback in a similar way to FM stereo. The great advantage of
CD4 was that separation between front and back was much greater than a
matrix system, and stereo and mono compatibility was excellent. The great
disadvantage of CD4 was that it didn't work! Under laboratory conditions,
with clean, unworn records it would work fine, but in the real world, with
records of varying cleanliness and wear, it would just collapse. Cartridges
had to track up to 45 kHz to recover the carrier and sidebands, and even one
playing by the blunderbuss cartridges fitted to most record players those
days would render the LP unplayable as a quad LP.

Different labels adopted different encoding standards. DSOTM was on EMI and
they used the SQ system as did CBS and, I think, did Decca, so a quad DSOTM
on EBay would be SQ encoded and you wouldn't need to worry about recovering
an HF carrier. If it's in good condition for stereo, the quad encoding
should also be in good condition.

Decoding SQ these days is pretty much impossible unless you can find a good
decoder dating back to the 70s. Sony made a few good ones the best probably
being the Tate decoder. As standard, the SQ system has only something like
7dB of crosstalk between L and R and only 3 dB between front and back if I
remember my matrix co-ordinates correctly. The later decoders had logic
steering to improve the subjective separation at the expense of wavering
positions.

The combination of three incompatible systems that never really worked
properly (there was a fourth, Dr. Duane Cooper's UD4, which however never
came to Europe in significant numbers)and the need for four loudspeakers
arranged in a square around the listener meant that the quadraphonic craze
only lasted a few years in the mid '70s.

If you want to find out more about quadraphonics in general, there's
http://www.quadraphonicquad.com/ which has information on the systems, a
forum etc.

S.

--
http://audiopages.googlepages.com

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Fleetie" wrote in message
...
Title lifted from an Ebay auction with Pink Floyd
search terms.

I've read a little about quad LPs recently. If my understanding
is correct, the encoding is a little like FM stereo in that there
is information encoded in HF above the audible range, and it's
something to do with sum-and-difference, that when decoded, yields the
rear channel information. How close am I?

I was surprised when I read that, since I assume a lot of that
information is above 20kHz, and quad was en vogue back in the 70s.
Were cartridges and preamps of the time capable of picking up signals
way in excess of 20kHz accurately?

Let's suppose I were to buy a Floyd DSOTM quad LP from Ebay:
Is there any equipment now that could take the output from
my cartridge and decode it? (Kinda irrelevant in fact because
I only have 2 speakers and a stereo amp, but... In the bottom of
my heart...) I would imagine that you can't easily get that kind
of gear any more.

Also, since the groove modulation extends to much higher frequencies
than it does with normal stereo, would playing it with a normal
cartridge/stylus be likely to cause it great (brain) damage (I use a
Sumiko Blue Point Special Evo III)?

How different was the back-channel information from the main
front signal? Could you, in practice, have 4 completely
different signals (vocals, for example) coming from the 4
speakers with very little crosstalk? Would the strident
tintinnabulation starting "Time" be different from each corner?


There were several different "Quadraphonic" systems, and I don't know which
Dark Side of the Moon used. The original quadraphonic system was the CBS
"SQ" system. This, like most of the others, (such as Sansui's "QS" and the
BBC's "Matrix H") was a "matrix" system in which four original audio tracks
were combined into two by a process of phase-shifting and combining, and
then separated again using phase-sensitive circuitry and gain-controlled
amplifiers. The most commercially successful of these systems is the Dolby
pro-logic system. Though this has been marketed as a surround-sound system,
not a quadraphonic one, it is essentially the same idea.

There was also the RCA "FM4" system, which seems to be the one you are
thinking of. This used a frequency-modulated carrier around 20kHz to carry
the band-limited rear channels.

With the matrix systems channel separation is very poor, hence the use of
gain controlled amplifiers which "enhance" the separation by reducing the
gain of the speaker channels into which the wanted signal has bled. Clearly
here it is NOT possible to carry 4 completely different signals.

With the RCA system in theory crosstalk should be very good (at least no
worse than normal disc stereo), but as you realised there were serious
problems with the sub-carrier at the top of the audio band. I had no
practical experience of this system, but I do remember that it didn't do
well commercially. If a record of this type is anything other than pristine
I would guess that the sub-carrier would be seriously reduced in amplitude
from it's new condition.

David.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

Thanks, Serge.

Interesting stuff. I kinda suspected that the records with
the HF encoding wouldn't've worked really work well with cartridges
of the time.

I was trying to decide whether it was worth buying the quad
version from Ebay, but you suggest what I suspected, which
was that it's basically impossible to get the quad info off
the vinyl and into my room these days.

I'll probably pass on it.


Thanks again.


Martin

Quadraphonic PINK FLOYD Dark Side of the Moon
 

Thanks David.

Yeah, you seem to be confirming what I suspected. Even these
days, I think it'd be hard to recover signal above 20kHz from
vinyl with good performance, so I'm still surprised they tried
it in the 70s and expected it to work *in*the*field* with the
domestic blunt-knitting-needle styli (for that's how it's spelt,
Jim Lesurf :-) ) of the day.

I don't think I'll bother buying the quad LP from Ebay.


Martin

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"David Looser" wrote in message
...

There was also the RCA "FM4" system,

Correction: "CD4", as Serge Auckland correctly stated. My fault for relying
on my 30-year old memories rather than looking it up!

David.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

In article , Serge Auckland
wrote:

"Fleetie" wrote in message
...


There were three basic encoding methods for quad records in the 70s. SQ
and QS were matrixed systems which means that the rear channels were
encoded essentially by phase differences in with the front channels.
This would make it reasonably compatible with normal stereo and almost
compatible with mono, important for broadcasting which was mostly on AM
in those days.

The third encoding method, which you allude to in your post was CD4,
which was a carrier system similar to FM in that the front plus rear
channels were mixed in the base-band, and the front-rear encoded on a
carrier and then decoded on playback in a similar way to FM stereo.

IIRC There was more than one 'ultrasonic subcarrier' system. UD-4 also
comes to mind.



The great advantage of CD4 was that separation between front and back
was much greater than a matrix system, and stereo and mono compatibility
was excellent. The great disadvantage of CD4 was that it didn't work!
Under laboratory conditions, with clean, unworn records it would work
fine, but in the real world, with records of varying cleanliness and
wear, it would just collapse. Cartridges had to track up to 45 kHz to
recover the carrier and sidebands, and even one playing by the
blunderbuss cartridges fitted to most record players those days would
render the LP unplayable as a quad LP.

I think the modulation survived moderatey well with one or two carts like
the one Shure did specially for CD4/UD4. But even then I have my doubts
about how many times the end of side could be played before becoming
undecodable. Systems like this seemed doomed from the start to me given the
struggle to play even modest hf levels with LP. Plus, of course, the way
companies at the time couldn't be bothered to take any care when pressing
LPs. Wonder how many LPs would have even had the subcarrier on the walls
when they popped out of the press. ;-

Different labels adopted different encoding standards. DSOTM was on EMI
and they used the SQ system

Not checked, But the 'quad' LP I used as a test disc for the work in the
webpage I put up today is an EMI one using SQ. So confirms the above.


The combination of three incompatible systems that never really worked
properly (there was a fourth, Dr. Duane Cooper's UD4, which however
never came to Europe in significant numbers)and the need for four
loudspeakers arranged in a square around the listener meant that the
quadraphonic craze only lasted a few years in the mid '70s.

Ah, as I recalled above.

IIRC Hi Fi News also did a double LP showing off 'quadrophony' by using a
different method for each LP side. No idea if anyone who bought it was
every able to play all four sides. :-)

Friend of mine at the time got keen on 4-channel (sic) so bought various
LPs, but only the SQ and QS types. But I was unimpressed, so stuck with
stereo.

IIRC There is now a surround-sound version of DSOTM on DVD. No idea how it
compares with the LP, and don't have a multichannel AV system so can't
check.

Slainte,

Jim

--
Change 'noise' to 'jcgl' if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Quadraphonic PINK FLOYD Dark Side of the Moon
 

In article , David Looser
wrote:
"Fleetie" wrote in message
...


With the RCA system in theory crosstalk should be very good (at least no
worse than normal disc stereo), but as you realised there were serious
problems with the sub-carrier at the top of the audio band. I had no
practical experience of this system, but I do remember that it didn't do
well commercially. If a record of this type is anything other than
pristine I would guess that the sub-carrier would be seriously reduced
in amplitude from it's new condition.

I can also recall at least one JAES paper discussing how to cope with the
large levels of intermod distortion between the audible and ultrasonic that
risked making the results such that decoding would fail, or be dreadful to
endure!

With the SQ and QS I imagine that someone could now write a computer
program that did the channel seperation in software, and you could then
playback or make a '4-channel' output. But I have no idea how many working
SQ/QS/H/etc decoders still exist in working order. IIRC one of the CD
lables (Unicorn?) did also produce matrix encoded CDs... May have one or
two somewhere...

Slainte,

Jim

--
Change 'noise' to 'jcgl' if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"David Looser" wrote in message
...
"Fleetie" wrote in message
...
Title lifted from an Ebay auction with Pink Floyd
search terms.

I've read a little about quad LPs recently. If my understanding
is correct, the encoding is a little like FM stereo in that there
is information encoded in HF above the audible range, and it's
something to do with sum-and-difference, that when decoded, yields the
rear channel information. How close am I?

I was surprised when I read that, since I assume a lot of that
information is above 20kHz, and quad was en vogue back in the 70s.
Were cartridges and preamps of the time capable of picking up signals
way in excess of 20kHz accurately?

Let's suppose I were to buy a Floyd DSOTM quad LP from Ebay:
Is there any equipment now that could take the output from
my cartridge and decode it? (Kinda irrelevant in fact because
I only have 2 speakers and a stereo amp, but... In the bottom of
my heart...) I would imagine that you can't easily get that kind
of gear any more.

Also, since the groove modulation extends to much higher frequencies
than it does with normal stereo, would playing it with a normal
cartridge/stylus be likely to cause it great (brain) damage (I use a
Sumiko Blue Point Special Evo III)?

How different was the back-channel information from the main
front signal? Could you, in practice, have 4 completely
different signals (vocals, for example) coming from the 4
speakers with very little crosstalk? Would the strident
tintinnabulation starting "Time" be different from each corner?


There were several different "Quadraphonic" systems, and I don't know
which Dark Side of the Moon used. The original quadraphonic system was the
CBS "SQ" system. This, like most of the others, (such as Sansui's "QS" and
the BBC's "Matrix H") was a "matrix" system in which four original audio
tracks were combined into two by a process of phase-shifting and
combining, and then separated again using phase-sensitive circuitry and
gain-controlled amplifiers. The most commercially successful of these
systems is the Dolby pro-logic system. Though this has been marketed as a
surround-sound system, not a quadraphonic one, it is essentially the same
idea.

The BBC's Matrix H was yet another matrix system, but one that came out of
Michael Gerzon et. al's work on ambisonics, and which was evaluated for
broadcast. The BBC did some test transmissions in Matrix H, but it never
went into full service as it didn't have full mono compatibility (something
the BBC was somewhat paranoid about at the time) and anyway, the whole quad
thing had pretty much gone away by then.

There was also the RCA "FM4" system, which seems to be the one you are
thinking of. This used a frequency-modulated carrier around 20kHz to carry
the band-limited rear channels.

You're thinking of CD4, which was the system used by RCA, JVC, Denon and
others. It was developed by JVC.

With the matrix systems channel separation is very poor, hence the use of
gain controlled amplifiers which "enhance" the separation by reducing the
gain of the speaker channels into which the wanted signal has bled.
Clearly here it is NOT possible to carry 4 completely different signals.

With the RCA system in theory crosstalk should be very good (at least no
worse than normal disc stereo), but as you realised there were serious
problems with the sub-carrier at the top of the audio band. I had no
practical experience of this system, but I do remember that it didn't do
well commercially. If a record of this type is anything other than
pristine I would guess that the sub-carrier would be seriously reduced in
amplitude from it's new condition.

David.


As one who lived and worked through the Quadraphonic era, it was a very
interesting time, and might have succeeded if there hadn't been three
competing and incompatible systems (UD4 was the fourth system, but it never
came to Europe). SQ and QS worked acceptably well for classical music and
jazz if ambiance only was recorded in the rear channels, giving a much
better impression of the venue. For rock music, I thought it worked less
well, given that producers wanted to use the surround for effect, swinging
instruments not only side to side, but also front-back and diagonally. With
the earlier non-logic decoders, crosstalk was so bad as to prevent accurate
localisation, and with the later logic-steered decoders, pumping effects
could be unpleasant. It's a great pity that Ambisonics never caught on, it
was being sponsored by the state-run NRDC at the time, with the predictable
result when marketing is handled by civil-servants. Of the competing
systems, SQ was probably the most successful commercially, but CBS, EMI and
others lost interest and never fully developed the potential.

Dolby later realised that what didn't work for music could well work for
movies, and launched the analogue matrixed Dolby Surround, which then led to
the discrete Dolby Digital we know and love.

S.

--
http://audiopages.googlepages.com

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Serge Auckland" wrote in message
...


The BBC's Matrix H was yet another matrix system, but one that came out of
Michael Gerzon et. al's work on ambisonics, and which was evaluated for
broadcast. The BBC did some test transmissions in Matrix H, but it never
went into full service as it didn't have full mono compatibility
(something the BBC was somewhat paranoid about at the time)

As I remember it a fair number of programmes were transmitted in Matrix H, I
still have a Matrix H off-air recording of "The Tempest" (the version
staring Paul Schofield, still my favourite version of the play).

and anyway, the whole quad thing had pretty much gone away by then.

There was also the RCA "FM4" system, which seems to be the one you are
thinking of. This used a frequency-modulated carrier around 20kHz to
carry the band-limited rear channels.

You're thinking of CD4, which was the system used by RCA, JVC, Denon and
others. It was developed by JVC.

Indeed, my mistake for relying on my memory rather than looking it up!


As one who lived and worked through the Quadraphonic era, it was a very
interesting time, and might have succeeded if there hadn't been three
competing and incompatible systems (UD4 was the fourth system, but it
never came to Europe). SQ and QS worked acceptably well for classical
music and jazz if ambiance only was recorded in the rear channels, giving
a much better impression of the venue. For rock music, I thought it worked
less well, given that producers wanted to use the surround for effect,
swinging instruments not only side to side, but also front-back and
diagonally.

QS was used for the initial release of the film of "Tommy" (with the
addition of a discrete centre channel) just the job for bouncing the pinball
sound around the cinema!

It's a great pity that Ambisonics never caught on,

I agree.

it was being sponsored by the state-run NRDC at the time, with the
predictable result when marketing is handled by civil-servants.

It also came too late.

Of the competing systems, SQ was probably the most successful
commercially, but CBS, EMI and others lost interest and never fully
developed the potential.

SQ was also the worst system (shades of VHS?) and was no advert for "quad".

Dolby later realised that what didn't work for music could well work for
movies, and launched the analogue matrixed Dolby Surround, which then led
to the discrete Dolby Digital we know and love.

Though of course Dolby Stereo (as it is known in cinemas) provides L, C, R
and (mono) surround, rather than LF, RF, LR and RR, which makes things a bit
easier, and used "logic" steering from the word go, at least in cinema use.

David.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

Fleetie wrote:

Thanks, Serge.

Interesting stuff. I kinda suspected that the records with
the HF encoding wouldn't've worked really work well with cartridges
of the time.

I was trying to decide whether it was worth buying the quad
version from Ebay, but you suggest what I suspected, which
was that it's basically impossible to get the quad info off
the vinyl and into my room these days.

The 'quad' effect was simply a gimmick anyway which is the biggest
reason of all it never gained popularity.

Graham

Quadraphonic PINK FLOYD Dark Side of the Moon
 

Fleetie wrote:

Thanks David.

Yeah, you seem to be confirming what I suspected. Even these
days, I think it'd be hard to recover signal above 20kHz from
vinyl with good performance, so I'm still surprised they tried
it in the 70s and expected it to work *in*the*field* with the
domestic blunt-knitting-needle styli (for that's how it's spelt,
Jim Lesurf :-) ) of the day.

I think you underestimate the cartridges of the day.

Graham

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Fleetie the ****wit "


Yeah, you seem to be confirming what I suspected. Even these
days, I think it'd be hard to recover signal above 20kHz from
vinyl with good performance, so I'm still surprised they tried
it in the 70s and expected it to work *in*the*field* with the
domestic blunt-knitting-needle styli (for that's how it's spelt,
Jim Lesurf :-) ) of the day.


** What the **** makes you think they ever did that ??

CD4 playback involved the use of a special PU cartridge fitted with a
special stylus (by Shibata ) - as well as the decoder unit. Google it.

BTW

Almost any modern * moving coil * cartridge operates to over 40 kHz.

What an ignorant **** you are.



....... Phil

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Fleetie" wrote in message
...
Thanks David.

Yeah, you seem to be confirming what I suspected. Even these
days, I think it'd be hard to recover signal above 20kHz from
vinyl with good performance, so I'm still surprised they tried
it in the 70s and expected it to work *in*the*field* with the
domestic blunt-knitting-needle styli (for that's how it's spelt,
Jim Lesurf :-) ) of the day.

**Incorrect. CD4 was the only decent quadraphonic system. QS and SQ were
severely limited 'kludges'. Worse, compatability with regular stereo was a
joke. I even kept a couple of SQ recordings, along with the regular stereo
ones as a comparison, to remind me of just how bad recording studios can get
it. A Shibata stylus could easily achieve what was required for CD4. Even on
a properly designed MM cart. MC carts can do better. MUCH better. By the
early 1980s, A decent MC could manage more than 60kHz. Correctly done,
record wear was somewhat more than a regular stereo recording. BTW: As
service manager for Marantz (Aust) during the 1970s, I needed to test 4
channel gear daily. Marantz manufactured both SQ and CD4 stuff. I had a
couple of CD4 records and a suitably equipped turntable (a Technics),
cartridge and stylus. Setting up the CD4 units required that I play a CD4
recording and note the existence of the carrier frequency and then perform a
listening test. Despite the records being played hundreds of times, the
carrier light always lit up, after alignment. I never much cared for 4
channel audio, but the descrete nature of CD4 was a vast improvement over
the SQ and QS systems.


I don't think I'll bother buying the quad LP from Ebay.

**I wouldn't, unless it was a nostalgia thing, or for an investment. Given
the shocking quality of most quadraphonic recordings, most people would have
disposed of them, thus ensuring their rarity and (possibly) pushing up
prices. They're sure not worth listening to.


--
Trevor Wilson
www.rageaudio.com.au

Quadraphonic PINK FLOYD Dark Side of the Moon
 

Serge Auckland wrote:

"David Looser" wrote in message
...
....
The BBC's Matrix H was yet another matrix system, but one that came out
of Michael Gerzon et. al's work on ambisonics, and which was evaluated
for broadcast. The BBC did some test transmissions in Matrix H, but it
never went into full service as it didn't have full mono compatibility
(something the BBC was somewhat paranoid about at the time) and anyway,
the whole quad thing had pretty much gone away by then.

The history of Matrix H and its relation to
Ambisonics is nicely described on Wikipedia
at:
http://en.wikipedia.org/wiki/Quadrophonic

The BBC produced Matrix H. This was
combined with Ambisonic 45J to give Matrix
HJ. This was then combined with UD-4/UMX to
give Ambisonic UHJ.

There was also the RCA "FM4" system, which seems to be the one you are
thinking of. This used a frequency-modulated carrier around 20kHz to
carry the band-limited rear channels.

You're thinking of CD4, which was the system used by RCA, JVC, Denon and
others. It was developed by JVC.

The rear channels of CD-4 were
full-bandwidth, not band-limited, so David
may have been thinking of UD-4.

It's a great pity that Ambisonics never caught on,

It is still around, and is currently
stronger than it has been for many years.
Visit www.ambisonia.com for over 100 pieces
available for free download. These are in
Ambisonic B-Format, and most are full-sphere.
You will need a software player to decode
the files. There are several available, all
free.

Also, visit my website (see Sig) for the
Ambisonic Surround Sound FAQ.

The original poster was interested in
obtaining a quad version of DSotM. If they
have a DVD burner then to find something
which might interest them, they should
Google for "dsotm torrent quad".

--
Regards,
Martin Leese
E-mail: LID
Web: http://members.tripod.com/martin_leese/

Quadraphonic PINK FLOYD Dark Side of the Moon
 

In article , Trevor Wilson
wrote:


"Fleetie" wrote in message
...
Thanks David.

Yeah, you seem to be confirming what I suspected. Even these days, I
think it'd be hard to recover signal above 20kHz from vinyl with good
performance, so I'm still surprised they tried it in the 70s and
expected it to work *in*the*field* with the domestic
blunt-knitting-needle styli (for that's how it's spelt, Jim Lesurf :-)
) of the day.

**Incorrect. CD4 was the only decent quadraphonic system. QS and SQ were
severely limited 'kludges'. Worse, compatability with regular stereo
was a joke. I even kept a couple of SQ recordings, along with the
regular stereo ones as a comparison, to remind me of just how bad
recording studios can get it. A Shibata stylus could easily achieve
what was required for CD4. Even on a properly designed MM cart. MC
carts can do better. MUCH better. By the early 1980s, A decent MC could
manage more than 60kHz.

The above unfortunately omits various significant practical details.

1) That being able to "manage" up to 60kHz doesn't simply mean being able
to detect tiny levels at that frequency. It also means being able to do so
at levels high enough for decent SNR and dynamic range. This sets demanding
limits on tip mass and mechanical impedance at ultrasonic HF. Not just a
matter of stylus profile.

2) That - as per JAES papers of the time - the requirement is also to have
low distortions with these extreme accelerations.

3) The awkward need for this to work right up to the end-of-side. Not just
at the start, or on a test band.

I'd be interested in any measured evidence that modern day MC carts could
play CD4 without wear and recover decent 4-channel. The main thing I notice
about many of them is the absence of data on things like mechanical
impedance or tip mass. One of the potential snags of MC is that a moving
coil might have more mass than a bit of metal modulating a reluctance... I
have wondered if people stopped mentioning this because the results might
be embarassing.

BTW You might find this month's 'Hi Fi News' of interest. Shows some
examples of where a fancy-named stylus profile does not ensure improved
performance. :-) Photos also show a stark difference between an old Shure
stylus and some modern examples.


Correctly done, record wear was somewhat more than a regular stereo
recording. BTW: As service manager for Marantz (Aust) during the 1970s,
I needed to test 4 channel gear daily. Marantz manufactured both SQ and
CD4 stuff. I had a couple of CD4 records and a suitably equipped
turntable (a Technics), cartridge and stylus. Setting up the CD4 units
required that I play a CD4 recording and note the existence of the
carrier frequency and then perform a listening test. Despite the records
being played hundreds of times, the carrier light always lit up, after
alignment. I never much cared for 4 channel audio, but the descrete
nature of CD4 was a vast improvement over the SQ and QS systems.

Well, I assume that other cartridges designed for the task also did it
fairly well. But being able to detect carrier is not the same as being able
to recover the information with the intended snr and distorion levels after
a number of playings. That said, I doubt the LP makers would have wept if
people had found they had to keep buying a fresh copy. ;-

Although one good result of the quadraphonic episode is that it did get
some stylus makers to work at developing ones with low tip mass. e.g. The
Shure M24H was developed in the mid-1970s specifically for replay quad LPs
including CD4, and had a declared tip mass of 0.39mg.


I don't think I'll bother buying the quad LP from Ebay.

**I wouldn't, unless it was a nostalgia thing, or for an investment.
Given the shocking quality of most quadraphonic recordings, most people
would have disposed of them, thus ensuring their rarity and (possibly)
pushing up prices. They're sure not worth listening to.

The few quad LPs I still have (or can find!) essentially sound like normal
stereo, but they are classical, so probably only have a touch of encoded
signal for ambience which passes unnoticed. I did use one of these for the
measurements I've just put onto audiomisc and these showed no obvious signs
that the recording was QS.

Slainte,

Jim

--
Change 'noise' to 'jcgl' if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Quadraphonic PINK FLOYD Dark Side of the Moon
 

In article , Fleetie
wrote:
Thanks David.

Yeah, you seem to be confirming what I suspected. Even these days, I
think it'd be hard to recover signal above 20kHz from vinyl with good
performance, so I'm still surprised they tried it in the 70s and
expected it to work *in*the*field* with the domestic
blunt-knitting-needle styli (for that's how it's spelt, Jim Lesurf :-) )
of the day.

The DSOTM is probably quite playable on modern kit. I'd be interested in
analysing a copy, but cannae be bothered to bid for it. :-)

I was always told it was 'stylii', though. Have I wandered into ped'ants
corner (Private Eye reference)? 8-]

Slainte,

Jim

--
Change 'noise' to 'jcgl' if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Eeyore" wrote in message
...



The 'quad' effect was simply a gimmick anyway which is the biggest
reason of all it never gained popularity.


A reason certainly, but the biggest? As I see it there were several
reasons:-

1/ Too many competing and incompatible systems.

2/ Cost

3/ Problems in accommodating rear speakers in the typical living room

4/ Unimpressive results (especially from the market leader SQ)

David.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

On Mon, 26 May 2008 09:38:48 +0100, Jim Lesurf
wrote:

In article , Fleetie
wrote:
Thanks David.

Yeah, you seem to be confirming what I suspected. Even these days, I
think it'd be hard to recover signal above 20kHz from vinyl with good
performance, so I'm still surprised they tried it in the 70s and
expected it to work *in*the*field* with the domestic
blunt-knitting-needle styli (for that's how it's spelt, Jim Lesurf :-) )
of the day.

The DSOTM is probably quite playable on modern kit. I'd be interested in
analysing a copy, but cannae be bothered to bid for it. :-)

I was always told it was 'stylii', though. Have I wandered into ped'ants
corner (Private Eye reference)? 8-]


Who led the pedants revolt? Which Tyler.

No, stylii would be the plural of stylius. But I believe the approved
plural is actually styluses.

d
--
Pearce Consulting
http://www.pearce.uk.com

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Don Pearce" wrote in message
...
On Mon, 26 May 2008 09:38:48 +0100, Jim Lesurf
wrote:

In article , Fleetie
wrote:
Thanks David.

Yeah, you seem to be confirming what I suspected. Even these days, I
think it'd be hard to recover signal above 20kHz from vinyl with good
performance, so I'm still surprised they tried it in the 70s and
expected it to work *in*the*field* with the domestic
blunt-knitting-needle styli (for that's how it's spelt, Jim Lesurf :-) )
of the day.

The DSOTM is probably quite playable on modern kit. I'd be interested in
analysing a copy, but cannae be bothered to bid for it. :-)

I was always told it was 'stylii', though. Have I wandered into ped'ants
corner (Private Eye reference)? 8-]


Who led the pedants revolt? Which Tyler.

No, stylii would be the plural of stylius.

Sylus is a noun of the second declension (m) model dominus.
The plural is styli.

But I believe the approved
plural is actually styluses.

Like Omnibuses ?

"Styluses" is "orrible" :-)

Iain

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Iain Churchus Congenital Mental Defective "


Sylus is a noun of the second declension (m) model dominus.
The plural is styli.


** ******** !!!!!!!!!!!!!

There is a Latin word " stilus " - but " stylus " is a word in the
English language.

The usual plural of which is " styluses " .

Just like the plural of " anus " is " anuses " - things the Churchus
autistic cretin is very familiar with.



....... Phil

PHIL IS AUTISTIC (Was Quadraphonic PINK FLOYD Dark Side of the Moon)
 

"Phil the Faggot"

Almost any modern * moving coil * cartridge operates to over 40 kHz.

What an ignorant **** you are.

** And I said I was surprised that OLD cartridges worked to
those frequencies.

If you'd actually READ what I wrote, you'd have realised that.

I know you're currently getting a ****ing ROASTING from others
in sci.elecectronics.basics (SEB), so that's why you're in such a
bad mood.

For the benefit of others: You all might wanna go have a look in SEB
to see Phil acting like a real **** and getting roasted because of
it.

Are you going to call me an autistic ****wit, now, Phil?

Phil, you do seem to use that insult a lot. It also seems to
me that you don't find it easy dealing with others at all, and
you frequently have inappropriate and disproportionate reactions
to what others say.

That makes me pretty sure that YOU are genuinely autistic, Phil.

What do you say to that question?

Eh, Phil?


Love and kisses,


Martin

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Phil Allison" wrote in message
...

Sylus is a noun of the second declension (m) model dominus.
The plural is styli.

There is a Latin word " stilus " - but " stylus " is a word in the
English language.

The Oxford Dictionary gives: Stylus (pl: styli)
Origin: Latin - stilus.

Both words follow the second declension model
dominus. "Sti", or "sty" is the stem, to which the
nominative plural ending "i" is added for stili or styli.

One can only have a double vowel ending (ii) with
a nous such as "radius", where "radi" is the stem to which
the ending "i" is added giving "radii"


The usual plural of which is " styluses " .

The Oxford dictionary states otherwise.

My ISP usually deletes your posts from the server
as soon as they appear. This one slipped through -
I must complain.

Antiquis temporibus, nati tibi similes in rupibus
ventosissimis exponebantur ad necem.

Iain

Iain Churchus= Congenital Mental Defective
 

"Iain Churchus = Congenital Mental Defective "


Sylus is a noun of the second declension (m) model dominus.
The plural is styli.

** ****ING ******** !!!!!!!!!!!!!

There is a Latin word " stilus " - but " stylus " is a word in the

** English language ** !!!


The Oxford Dictionary gives: Stylus (pl: styli)
Origin: Latin - stilus.

Both words follow the second declension model
dominus.

** WRONG language - YOU ****ING IDIOT !!!!!

The word "stylus " NOT Latin - ****WIT !!

So you cannot apply the rules of Latin to it - ****WIT !!!



The usual plural of which is " styluses " .

The Oxford dictionary states otherwise.


** Like hell it does - ****WIT !!

Most folk use " styluses" as the plural of "stylus" ( over 2.3 million
hits on Google) and most dictionaries give it as one of the two
alternatives.

Go D R O P D E A D !!!!

you sub human pile of criminal GARBAGE !!




...... Phil

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Iain Churches" wrote in message
i...

Both words follow the second declension model
dominus. "Sti", or "sty" is the stem, to which the
nominative plural ending "i" is added for stili or styli.

Correction. "Stil" or "styl" is the stem.....

Iain

Iain Churchus= Criminal Mental Defective
 

Iain Churchus = Congenital Mental Defective "


Both words follow the second declension model
dominus.

** ****ING ******** !!!!!!!!!!!!!

There is a Latin word " stilus " - but " stylus " is a word in the

** English language ** !!!

The word "stylus " NOT Latin - ****WIT !!

So you cannot apply the rules of ****ing Latin to it - ****WIT !!!


Fact:

Most folk use " styluses" as the plural of "stylus" ( over 2.3 million
hits on Google) and most dictionaries give it as one of the two
alternatives.

Go D R O P D E A D !!!!

you sub human pile of criminal GARBAGE !!



...... Phil

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"David Looser" wrote in message
...
"Eeyore" wrote in message
...



The 'quad' effect was simply a gimmick anyway which is the biggest
reason of all it never gained popularity.


A reason certainly, but the biggest? As I see it there were several
reasons:-

1/ Too many competing and incompatible systems.

2/ Cost

3/ Problems in accommodating rear speakers in the typical living room

4/ Unimpressive results (especially from the market leader SQ)

David.


Indeed. Quadraphonics was no more a gimmick than stereo was to mono. It was
meant to improve the listening experience. The above reasons for failure are
pretty much spot-on, and in the right order.

S.

--
http://audiopages.googlepages.com

Quadraphonic PINK FLOYD Dark Side of the Moon
 

Jim Lesurf wrote:

IIRC There is now a surround-sound version of DSOTM on DVD. No idea how it
compares with the LP, and don't have a multichannel AV system so can't
check.

Hmmm. Dark side of the moon.... Just take the drugs. Ye'll get more than
a few channels and some pretty colours as well ;-)

--
Adrian C

Quadraphonic PINK FLOYD Dark Side of the Moon
 

Fleetie wrote:


Would the strident
tintinnabulation starting "Time" be different from each corner?


I don't recall ever hearing the record in quad but it's probably one of
the few things worth releasing in quad since that is how it was
performed live.

Serge is right though, Ambisonics is the only "proper" surround system.

Yours, not-old-enoughly-but-very-nearly,

I am. I saw it performed live before the album came out. The memory is
vivid after many years. I'll probably still remember it when I'm
dribbling down my shirt in the old folks home. Trouble is they'll
probably be playing me Frank Ifield.

Roy.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

On Mon, 26 May 2008 02:57:54 GMT, Martin Leese
wrote:

Serge Auckland wrote:

"David Looser" wrote in message
...
...
The BBC's Matrix H was yet another matrix system, but one that came out
of Michael Gerzon et. al's work on ambisonics, and which was evaluated
for broadcast. The BBC did some test transmissions in Matrix H, but it
never went into full service as it didn't have full mono compatibility
(something the BBC was somewhat paranoid about at the time) and anyway,
the whole quad thing had pretty much gone away by then.

The history of Matrix H and its relation to
Ambisonics is nicely described on Wikipedia
at:
http://en.wikipedia.org/wiki/Quadrophonic

The BBC produced Matrix H. This was
combined with Ambisonic 45J to give Matrix
HJ. This was then combined with UD-4/UMX to
give Ambisonic UHJ.

There was also the RCA "FM4" system, which seems to be the one you are
thinking of. This used a frequency-modulated carrier around 20kHz to
carry the band-limited rear channels.

You're thinking of CD4, which was the system used by RCA, JVC, Denon and
others. It was developed by JVC.

The rear channels of CD-4 were
full-bandwidth, not band-limited, so David
may have been thinking of UD-4.

It's a great pity that Ambisonics never caught on,

It is still around, and is currently
stronger than it has been for many years.
Visit www.ambisonia.com for over 100 pieces
available for free download. These are in
Ambisonic B-Format, and most are full-sphere.
You will need a software player to decode
the files. There are several available, all
free.

Also, visit my website (see Sig) for the
Ambisonic Surround Sound FAQ.

The original poster was interested in
obtaining a quad version of DSotM. If they
have a DVD burner then to find something
which might interest them, they should
Google for "dsotm torrent quad".

Does anyone remember the BBC's late night experiments in 4 channel
sound in the early 70's? They used 2 stereo FM channels.

Or for that matter their late 50's stereo tests on a Saturday morning
using BBC TV sound and BBC Third Programme as the two channels. I
remember my dad moving the (very large) radiogram into the correct
position......and my mother's horror!

John J Armstrong

Quadraphonic PINK FLOYD Dark Side of the Moon
 

In article ,
Serge Auckland wrote:
A reason certainly, but the biggest? As I see it there were several
reasons:-

1/ Too many competing and incompatible systems.

2/ Cost

3/ Problems in accommodating rear speakers in the typical living room

4/ Unimpressive results (especially from the market leader SQ)

David.


Indeed. Quadraphonics was no more a gimmick than stereo was to mono. It
was meant to improve the listening experience. The above reasons for
failure are pretty much spot-on, and in the right order.

I'd not agree. Stereo, recorded on a simple mic pair - in a good listening
room - gives a good soundstage between and sometimes outside the actual
speakers. Quad - using four mics, and four speakers in the same sort of
way simply doesn't work properly - you get little to no side information,
and the rear isn't brilliant either. The only decent true surround I've
ever heard is Ambisonics - and that is a very much more expensive device
to implement than pure 'quad'.

As regards the extra speakers needed for quad it doesn't seem to have put
off the numbers who now have AV setups.

--
*If one synchronized swimmer drowns, do the rest have to drown too?

Dave Plowman London SW
To e-mail, change noise into sound.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

In article ,
John J Armstrong wrote:
Or for that matter their late 50's stereo tests on a Saturday morning
using BBC TV sound and BBC Third Programme as the two channels. I
remember my dad moving the (very large) radiogram into the correct
position......and my mother's horror!

I do indeed remember them. And given how important accurate phase is
across the full frequency range for decent stereo I wonder why they even
bothered.

--
*People want trepanners like they want a hole in the head*

Dave Plowman London SW
To e-mail, change noise into sound.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Phil Allison" wrote in message
...

Iain wrote
Both words follow the second declension model
dominus.


I deleted the parts of Phil's posts that contained
expletives. There was nothing left.

A local wit just asked me:

Q. What is the Latin nominative plural for
"Socially-challenged Australian toaster repairer" ?

A. There is no plural. There is only one Phil Allison.


Iain

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Iain Churches" wrote
I deleted the parts of Phil's posts that contained
expletives. There was nothing left.

A local wit just asked me:

Q. What is the Latin nominative plural for
"Socially-challenged Australian toaster repairer" ?

A. There is no plural. There is only one Phil Allison.

Iain

He's absolutely furious that I have outed his autism, when
he's been using that as his most common insult to others -
deploying it as "chaff" to distract attention to his own
suffering from that socially-crippling condition. And that's
quite obviously what his problem is - he just doesn't have
normal social reactions to people and cannot control himself.
He cannot understand social interaction, and struggles
constantly trying to make sense of other people, and emotions.

He didn't reckon on the fact, when he was rude to me, that
I have a SERIOUSLY nasty streak, pretty much psycopathic,
in fact, and I can have a lot of fun taunting him and making
him foam at the mouth, as I rattle his cage.

And since he seems to have to have the last word, I reckon
there's a good chance he'll keep coming back for more.

The smart thing for him to do would be to shut the hell up,
because I'm nasty enough that I won't necessarily soon tire
of humiliating and teasing him.

I'm going to enjoy it.


Martin

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Fleetie" wrote in message
...

He didn't reckon on the fact, when he was rude to me, that
I have a SERIOUSLY nasty streak, pretty much psycopathic,
in fact, and I can have a lot of fun taunting him and making
him foam at the mouth, as I rattle his cage.


I just kill-filed the idiot as soon as I realised that all his posts were
simply expletive-laden insults, seems the easiest way. Why bother rattling
his cage, is he worth it?

David.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"David Looser" wrote
I just kill-filed the idiot as soon as I realised that all his posts were
simply expletive-laden insults, seems the easiest way. Why bother rattling
his cage, is he worth it?

Because my psycopathic streak enjoys it.

It's entertainment. That's all. No better reason than that.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"John J Armstrong" wrote in message
...

Does anyone remember the BBC's late night experiments in 4 channel
sound in the early 70's? They used 2 stereo FM channels.

Oh yes. My brother and I combined our HiFi systems to listen to them. Some
material came over very well, I particularly remember a Van Morrison
session.

Or for that matter their late 50's stereo tests on a Saturday morning
using BBC TV sound and BBC Third Programme as the two channels. I
remember my dad moving the (very large) radiogram into the correct
position......and my mother's horror!


And yes again! Hearing one channel from a large pre-war Murphy radio with
energised speaker and the other from a 1950s Ultra TV with "wrap-around"
cabinet and small side facing speaker driven with around 500mW by the
pentode half of a 30FL1 (would you believe that the triode section was part
of the field oscillator?) didn't give optimum channel balance.

David.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

"Dave Plowman (News)" wrote in message
...

As regards the extra speakers needed for quad it doesn't seem to have put
off the numbers who now have AV setups.


There's a vast difference between the rear speaker problem for 1970's quad
and that for 21st C "home cinema". The surround speakers of AV do not need
either the frequency range or the acoustic output capability of the main
front speakers, whilst the rear speakers for quad really needed to be a
match for the front ones. And you can sit close to the rear speakers without
it spoiling the soundstage, partly because the rear speakers carry only
ambience, or rear-only effects and partly because AV surround decoders delay
the signal to the surround speakers to ensure that time co-incident sounds
are heard from the front speakers first. With quad the rear speakers needed
to be about as far behind the listening position as the front speakers were
in front of it otherwise the soundstage collapsed. This, I would suggest,
was, and is, difficult to do in typical living rooms.

David.

Quadraphonic PINK FLOYD Dark Side of the Moon
 

In article ,
David Looser wrote:
As regards the extra speakers needed for quad it doesn't seem to have
put off the numbers who now have AV setups.


There's a vast difference between the rear speaker problem for 1970's
quad and that for 21st C "home cinema". The surround speakers of AV do
not need either the frequency range or the acoustic output capability
of the main front speakers, whilst the rear speakers for quad really
needed to be a match for the front ones. And you can sit close to the
rear speakers without it spoiling the soundstage, partly because the
rear speakers carry only ambience, or rear-only effects and partly
because AV surround decoders delay the signal to the surround speakers
to ensure that time co-incident sounds are heard from the front
speakers first. With quad the rear speakers needed to be about as far
behind the listening position as the front speakers were in front of it
otherwise the soundstage collapsed. This, I would suggest, was, and is,
difficult to do in typical living rooms.

Quite so as a theory - but how many have even the main pair of speakers in
the correct place- let alone 4? My guess is quad was simply not good
enough to warrant the extra expense. I was never tempted by any
demonstrations - unlike just about everything else. ;-)

--
*I didn't fight my way to the top of the food chain to be a vegetarian.

Dave Plowman London SW
To e-mail, change noise into sound.

Iain Churchus= Congenital Autistic Menace
 

"Iain Churchus = Congenital Mental Defective "

Sylus is a noun of the second declension (m) model dominus.
The plural is styli.

** ****ING ******** !!!!!!!!!!!!!

There is a Latin word " stilus " - but " stylus " is a word in the

** English language ** !!!


The Oxford Dictionary gives: Stylus (pl: styli)
Origin: Latin - stilus.

Both words follow the second declension model
dominus.

** WRONG language - YOU ****ING IDIOT !!!!!

The word "stylus " NOT Latin - ****WIT !!

So you cannot apply the rules of Latin to it - ****WIT !!!



The usual plural of which is " styluses " .

The Oxford dictionary states otherwise.


** Like hell it does - ****WIT !!

Most folk use " styluses" as the plural of "stylus" ( over 2.3 million
hits on Google) and most dictionaries give it as one of the two
alternatives.

Go D R O P D E A D !!!!

you sub human pile of criminal GARBAGE !!



...... Phil