Commercial Matrix Quadraphonic Cassettes?

[fizzywiggs41]

I posted some of these cassettes with quadraphonic indication elsewhere, so I thought I'd feed this thread particular to their need.

 

[fizzywiggs41]

And some cassettes that are definitely quad but these cassettes like most early cassettes do not contain liner notes . That's something I always found disappointing, and I think European cassettes offered more in the way of liner note information. (This was also true of a number of early cds).


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[fizzywiggs41]

Rummaging through my closet the other day , and what do you know ,........
I do have some of those Angel SQ Quad cassettes !
Such as these which have been found...

 

[fizzywiggs41]

And a few more...one on Seraphim, one on Columbia Record Club , and some reissues on Angel/EMI/Redline.

 

[Owen Smith]

Surely for single inventory stuff any cassette release would be matrix encoded. So there should be plenty of matrix encoded commercial cassettes.

 

[kfbkfb]

Any of these matrix encoded surround sound prerecorded cassettes mention to be sure to apply the appropriate NR on playback prior to matrix decoding?

Anyone tried QS or SQ decoding with a Dolby B NR encoded QS or SQ encoded cassette with no NR decoding (does the level dependent frequency response of Dolby B NR confuse the decoder)?


Kirk Bayne

 

[ClassicalSurroundFan]

Is there a list of these releases anywhere?

 

[ClassicalSurroundFan]

Rummaging through my closet the other day , and what do you know ,........
I do have some of those Angel SQ Quad cassettes !
Such as these which have been found...

View attachment 99846

This is really interesting! Surely some CDs or even streaming content fall into the same category which is even more interesting. It seems the Saint Saens 3 and Bruckner 9 were not released as quad vinyl though, at least in the editions I could see on eBay.

 

[Owen Smith]

This is really interesting! Surely some CDs or even streaming content fall into the same category which is even more interesting. It seems the Saint Saens 3 and Bruckner 9 were not released as quad vinyl though, at least in the editions I could see on eBay.

There are loads of CDs which are matrix encoded, but there is almost never any mention on the packaging of the encoding. And sometimes the matrix encoding has been damaged by aggressive EQ for the CD release, only zero phase change EQ will leave the encoding alone. The same applies to streaming, plus concerns about lossy compression (which includes MQA).

Cassettes generally don't decode well, it isn't a good enough playback mechanism with channel separation and head azimuth issues. CD is much better for this, usually better than the original matrix LP.

 

[Soundfield]

It seems the Saint Saens 3 and Bruckner 9 were not released as quad vinyl though, at least in the editions I could see on eBay.

The Giulini Bruckner 9 was widely released in SQ vinyl across all of EMI's labels e.g.-

Label: Angel Records
Cat#: S-37287, EAC-80385
Label: Die Stimme Seines Herrn
Cat#: 1 C 063-02 885 Q
Label: His Master's Voice
Cat#: ASD 3382, 063-02 885 Q
Label: La Voce Del Padrone
Cat#: 3 C 065 02885 Q

 

[MidiMagic]

The circle logo on Angel means quadraphonic SQ.

I have many records, cassettes, and CDs that are movie soundtracks and at least parts of them are in Dolby Surround because the sound was taken directly from the film.

SQ is a lot more susceptible to interference from the lack of Dolby B decoding than the RM systems are.

 

[par4ken]

Any of these matrix encoded surround sound prerecorded cassettes mention to be sure to apply the appropriate NR on playback prior to matrix decoding?

Anyone tried QS or SQ decoding with a Dolby B NR encoded QS or SQ encoded cassette with no NR decoding (does the level dependent frequency response of Dolby B NR confuse the decoder)?


Kirk Bayne

I doubt that. In any case it should not mater. The noise reduction process effects both channels equally. A bigger problem would be if the machines head alignment (azimuth) doesn't match that of the machine that the tape was made on.

Edit: I was thinking about NR schemes such as DBX where the two channels are linked to prevent the stereo image from shifting.
Dolby AFAIK each channel operates independently. In any case it affects the high end only and so should not make a huge difference. Most encoded cassettes were single inventory so likely were mostly played in stereo only.

 

[kfbkfb]

I tried something similar recently - I recorded some of the Dolby Surround test signals from my Delos test CD - type 1 tape, Dolby B on, played back with Dolby B off, (original) DPL - imaging was good, maybe DPL is more robust than QS or SQ?

I'd be interested in the result with QS/SQ encoded music or test signals (record: type 1 tape + B on, play: B off) played through a no logic decoder and then a logic decoder (probably variable matrix).


Kirk Bayne

 

[par4ken]

imaging was good, maybe DPL is more robust than QS or SQ?

I think that the NR just effects the top end, directional effects will be noticed mainly in the mid band. DPL (original Dolby Surround) might be a bit more "robust" as it is bandlimited and has only one surround channel.

 

[fizzywiggs41]

Is there a list of these releases anywhere?

See post #19 of this thread..........and also The Quadraphonic Discography.

 

[Owen Smith]

I think that the NR just effects the top end, directional effects will be noticed mainly in the mid band. DPL (original Dolby Surround) might be a bit more "robust" as it is bandlimited and has only one surround channel.

The mono summing and band limiting of the surround channel is on playback and only for original DPL. Pro Logic II decodes exactly the same encoded source, but with stereo surrounds and no band limiting. I don't see how artificial limitations on playback would make it more robust.

 

[par4ken]

I don't see how artificial limitations on playback would make it more robust.

Just that anomalies or imbalances (with NR) would be mainly at the high end only which is mostly filtered out anyway with original DPL, which is what (I think) kbfkfb is concerned about.

PLII should produce similar results as the other two as it is related to both but is closer to QS.

 

[kfbkfb]

https://www.worldradiohistory.com/A...idelity/80s/High-Fidelity-1988-02.pdf#page=45(recently discussed NR systems in Tapeheads.net)


AFAIK, the stereo imaging errors caused by Dolby B NR stereo cassettes played back without NR decoding haven't been discussed, I might copy some test music from my Chesky CD (B NR on record, off play), specifically the LEDR stereo tests:
https://www.discogs.com/release/156...Sampler-Audiophile-Test-Compact-Disc-Volume-1

My RCA Dolby Surround encoded cassette is also Dolby S NR encoded [said to partially decode with Dolby B NR], will try that soon using original DPL (B NR on, then off).


Kirk Bayne

 

[doriangrey63]

Rummaging through my closet the other day , and what do you know ,........
I do have some of those Angel SQ Quad cassettes !
Such as these which have been found...

View attachment 99846

They are simple audio cassettes, in which the recording technique has been improved, but the result is the same, stereo sound that wears out and fades over time, but that sound somewhat better than those recorded with standard techniques.

 

[par4ken]

They are simple audio cassettes, in which the recording technique has been improved, but the result is the same, stereo sound that wears out and fades over time, but that sound somewhat better than those recorded with standard techniques.

Yes they are simple stereo cassettes but ones on which the original program has been SQ Quadraphonic encoded which is why fizzy is interested in them. They won't necessarily sound better than an unencoded recording in stereo playback. Some critics complained about the "foggy" sound quality of SQ. Others like myself rather like the sound, especially with headphone listening.