CD-4 Cartridge Stylus Recommendations

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Quad D:
I see by your equip list that you have a Sansui quad receiver - have you tried the QS decoder with the albums you mentioned previously (played using a CBS SQ decoder)?


Kirk Bayne
I did try QS, but I get more response using SQ in almost every case. I have, for example, both CD-4 and half speed mastered versions of Doobie's Captain and me, and regular version played through SQ sounds 70% as discrete as CD-4 version using CD-4 decoder. I can't explain it other than regular mix having so much out of phase information panned left and right in front channels, that SQ decoder picks it up and places it back. Even if not entirely correct, it is very pleasing nonetheless. But I am using a cartridge with very high stereo separation, it certainly helps.A lot of early Steely Dan albums perform similarly (they also sound decent using QS). Paul Simon early albums are SQ quadraphonic even in stereo versions. And the list goes on. For a while I had both Dolby Pro and DTS Neo decoders in same system as Sansui SQ and QS, and I compared them, and in my opinion using SQ and QS for regular stereo sources is not that different than using Dolby and DTS for the same. With analog sources I much preferred SQ and QS, so I left it at that.
 
I was referring to regular stereo non CD-4 version, that might have seen a trip through the SQ encoder as a simpler way of getting decent sounding stereo record than the remixing from 4 channels to two. In case the studio original mix is 4 ch format.
Companies that went with CD-4 would have had nothing to do with SQ (at least not both at the same time). However CBS built an encoder that had a stereo to SQ mode. It was intended for FM stations broadcasting in quad to fill in their schedule with "synthesized quad". It is essentially a forward oriented SQ encoder. It works in a similar manner as the Stereo Enhance (Audionics) and Surround (Fosgate Tate II) decoder modes.

The same encoder could be used to convert (encode) discrete sources to SQ encoded ones. I don't know how much it was ever used or by how many stations. Sansui built a QS encoder for the same purpose.

Some companies like the German Bellaphon/Bacillus Records released everything in SQ for awhile with no separate stereo version and IMHO those albums sound fine in stereo. Had all record companies done that (single inventory quad) there would have been a huge amount of software available and Quad might have had a much better chance of survival!
 
I did try QS, but I get more response using SQ in almost every case. I have, for example, both CD-4 and half speed mastered versions of Doobie's Captain and me, and regular version played through SQ sounds 70% as discrete as CD-4 version using CD-4 decoder. I can't explain it other than regular mix having so much out of phase information panned left and right in front channels, that SQ decoder picks it up and places it back. Even if not entirely correct, it is very pleasing nonetheless. But I am using a cartridge with very high stereo separation, it certainly helps.A lot of early Steely Dan albums perform similarly (they also sound decent using QS). Paul Simon early albums are SQ quadraphonic even in stereo versions. And the list goes on. For a while I had both Dolby Pro and DTS Neo decoders in same system as Sansui SQ and QS, and I compared them, and in my opinion using SQ and QS for regular stereo sources is not that different than using Dolby and DTS for the same. With analog sources I much preferred SQ and QS, so I left it at that.
Years ago my decoder was the Audionics 106A. It was a basic unit with no logic circuitry. I ran everything through it and loved it! The effect was not discrete in any way but it was what was then often referred to as surround sound. Stereo from the front with sort of a wash of phase shifted sound surrounding you. QS even sounded good through it!

So I get what you are saying and I fully agree about SQ and QS producing a much more pleasing effect than Dolby!
 
Years ago my decoder was the Audionics 106A. It was a basic unit with no logic circuitry. I ran everything through it and loved it! The effect was not discrete in any way but it was what was then often referred to as surround sound. Stereo from the front with sort of a wash of phase shifted sound surrounding you. QS even sounded good through it!

So I get what you are saying and I fully agree about SQ and QS producing a much more pleasing effect than Dolby!
I definitely had a similar setup. A decent stereo system with a Sony SQD-1000 decoder, and I ran everything through it, and thought it was groovy as all-get-out.
 
Pick Up The Pieces sounds pretty good even in stereo version when played through SQ decoder. Happens to me a lot, Doobie Brothers quad albums (CD-4) sound almost the same quadrophonic when played through SQ. Maybe there was a pass through SQ encoder during stereo mastering, since it was recorded in 4 channel. A little too much for the accidental out of phase pickup by SQ decoder during playback.
Would be interesting to try the upcoming Quadios, the stereo track on the Blu-ray, and see how it sounds in SQ.
 
Aside:
The Sansui QS (sometimes also called RM) matrix decoder is generally considered to provide better fake surround sound from any stereo source - disc[including the compatible stereo/sum signal on CD-4 discs]/tape/radio/streaming than the CBS SQ matrix decoder.


Off topic:
IMHO, it would have been a cost saving idea to make only the quad mix of an album (for CD-4/Q8/Q4) and use the Electro-Voice Stereo-4 matrix system to encode this same quad mix into stereo for stereo releases of the album (maybe not mention the Stereo-4 encoding by name - call it Stereo+)


It is unlikely that the proponents of CD-4 would have allowed the compatible stereo/sum signal to be matrix encoded (any system).


I am interested in how well the AT-VM95SH works for CD-4, anyone tried it (especially on the inner grooves of CD-4 discs)?


Kirk Bayne
Leonard Feldman proposed this in "Why the Four Channel War need not Take Place" in
Audio 06/1972 pp. 30-32.

He provided a set of equations for the EV system and for the SQ system to matrix the discrete record.

But the reason each company developed its own system was that they did not want to have to pay royalties on some other system.
 
I think that Len was just musing about that possibility which was unlikely to happen when each corporation had their own invested interest in their own system. UD-4 did use that idea of matrix + discrete but was virtually unheard of outside of Japan.
 
I suspect its down to the fact that CD4 is actually like 2 FM radio stations so it is 'matrixed' in away. The unmodulated 'stereo' signals are LF+LR & RF+RR (The FM modulated upper bands are LF-LR & RF-RR) so the Matrix decoders can work quite well with the 'stereo' signal pair.
Playing a CD-4 record through a matrix decoder would be just like playing a stereo record the same way. You can get a quad effect, but it won't be even close to the same as the real quad mix.
 
There’s obviously nothing technical to prevent a label from using both a carrier and a phase-encoded matrix on an LP. I often wished the CD-4 recordings had done that, because CD-4 represented quite an additional investment over the SQ system I already had in place.

Of course, patents and licensing cause all sorts of legal complications (I was a patent examiner for several years), so the likelihood of such a release was slim, but it always seemed to me to be a lost opportunity.
 
Playing a CD-4 record through a matrix decoder would be just like playing a stereo record the same way. You can get a quad effect, but it won't be even close to the same as the real quad mix.
Absolutely, but there may possibly be more out of phase signal due to the Quad mix, conversely there might not be, so its hit & miss as to what appears
 
My concern would be that by adding the discrete subcarrier information to the matrix record you would reduce the overall fidelity of the recording.

The other sticking point would be which matrix system to use. You would would have to pick one that would be baked into the system from the beginning. People still don't on agree which is best (SQ vs QS).

Such a system would be a compromise. When it comes to audio I hate compromise!

Had the powers that be kept Quad alive a bit longer we would have had discrete CD's!
 
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Such a system would be a compromise. When it comes to audio I hate compromise!

Had the powers that be kept Quad alive a bit longer we would have had discrete CD's!
Every system is a compromise. Hell, every component in every circuit is a compromise.

And the RBCD spec includes a quad format, although nobody’s ever seen one made that way.
 
I must search my A/V brochure "archive" again (sorta organized in my basement) for the Philips CD brochure I picked up at the 1981 summer CES in Chicago, IIRC, it says that discrete quad was planned for the CD, but with 1/2 the playing time of a stereo CD (IMHO, the only reasonable interpretation of this statement is that the CD quad would be 16bits/44.1kHz x 4).

It was surprising to see quadraphonic sound mentioned in 1981 (Dolby MP matrix decoders were still about 1 year in the future).


Kirk Bayne
 
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It was surprising to see quadraphonic sound mentioned in 1981
Not surprising at all. Audionics was still making the S&IC and Fosgate either the Tetrasound or Tate II. Those small companies were undaunted by what the majors were doing (or rather not doing).

We believers were strongly encouraged by the development of these super decoders as well as the prospect of quad CD's. Sad that multi-channel audio took a detour via video!
 
What killed quad was a disparity between sales in Q4 reel recorders and all the rest of the quad equipment. Q4 equipment was booming, the rest was languishing. Then, in 1976, they found out that most of the Q4 equipment was going into homebrew recording studios, nor quad use (As a repairman, I already knew this).

The executives of one record company got so mad that they ordered everything they had made for quad destroyed.
 
What killed quad was a disparity between sales in Q4 reel recorders and all the rest of the quad equipment. Q4 equipment was booming, the rest was languishing. Then, in 1976, they found out that most of the Q4 equipment was going into homebrew recording studios, nor quad use (As a repairman, I already knew this).

The executives of one record company got so mad that they ordered everything they had made for quad destroyed.
You spoke of this before and I still disagree with you. The fact that many of those quad reels were being used for another purpose was a positive thing. That kept production going with new models added for a time. Those machines had useful new features like sound with sound allowing you to record while monitoring channels that were already recorded.

That did not destroy or hurt quad in any way.
 
IIRC, Panasonic (and JVC) and Sony hadn't mentioned Quad sound since about 1977 (IIRC, a Sansui quad receiver ad in mid-1978 was the last mainstream mention of quad sound).

In 1981, Philips was a big consumer electronics company, to see them specifically use the word quadraphonic as a desirable option in their new CD system was surprising and encouraging (that they were still interested in surround sound for home audio systems), anyway...what might have been...


Kirk Bayne
 
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