Matrix vs Discrete

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We now have a number of discrete formats to champion what was supposed to be true quad and surround.
So I can't say that CD 4 was even comparable, to actual discreet , as intended.
CD-4 at it's best provided 20dB which was once considered perfect separation. Reading the promo brochures and or the reviews of the Space and Image Composer from years ago they liked to point out that the S&IC provided 35 dB separation compared to CD-4 at 20 dB (10 to 1) separation. They even suggested decoding those (CD-4 records) via the Composer rather than demodulating them. They failed to consider that the foldown of the discrete mix may not decode as well as a stereo mix would and will certainly not be what was intended. Still it was like the shoe now being on the other foot separation wise, where prior the CD-4 folk used to denigrate the (poor) separation of matrix.

I always wished that the two groups would have worked together supporting each others efforts. We could've had discrete in the eighties via the CD if the industry would have hung in there a bit longer. There was (back then) room for both discrete and matrix then there still is now. By criticizing each others efforts they cast a shadow of negativity around quad in general.

I spent a lot of time over the years to get CD-4 to work properly and am very close now. Despite being able to play CD-4 acceptably you are right that there is little comparison with modern sources like the Quadios, true discrete for sure!
 
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Nice to see that this discussion now has its own topic...

Whether we like it or not, given that we now live in a digital audio world it's discrete (over matrix) audio all the way for me :)
Again, it should not really be one over the other. Matrix decoders are still very useful (IMHO invaluable) in extracting surround from stereo.
 
This brings up a question, Chucky. I use the Evaluation Encoder module... is it also tri-band? My encodings sound damn good, and it would be nice to know I'm tri-band on both ends.
Yep its the full show, triband with full phycho acoustic stuff.
 
On that note, imagine having Involve's Surround Master circuitry included in a receiver or processor... that's the ultimate!
Try finding the front door of the major manufacturers, it does not exist. Its like trying to talk to a politician in Australia, you get the bums rush unless you have a Lobbyist with an orange card costing you a starting $10K a month (we have done that on our other company)
 
For me it was always the magic of matrix.
4 channels ,with 2 hidden in the stereo mix , to be extracted with a decoder.
And decoders added realistic depth and ambient music , which could be sometimes superior to the Discrete mix , just as quad recording of Santana LOTUS has proven.

And then the incredible Synthesis of older stereo recordings with a decent quad decoder.Some sounded so good in Synthesis matrix , you almost swore it was a purposeful quad recording.
And today those decoders are still very much relevant.

Discreet Demodulators , CD 4, were very picky and carried a high pitch noise signal with the proper cartridge. When they worked , (but never with every track on the vinyl LP ) , they sounded very good as was intended. I never experienced a single vinyl CD 4LP that was perfect, noise free , but it did get close at times.

We now have a number of discrete formats to champion what was supposed to be true quad and surround.
So I can't say that CD 4 was even comparable, to actual discreet , as intended.

But I can say with a good decoder , I find matrix to be most appealing, and close enough to sound discrete , not perfection , but darn near. And I do not seek perfection , just a great sounding recording.
SPOT ON
 
Since the late seventies early eighties I've seen very few turntables with the 78 speed. Again not a problem, if you need 78 just stick to vintage.

I know that I'm drifting away off topic but I actually built a speed control for my turntable from an Audio Amateur article by Gary Galo. It works only on synchronous motors and is just an audio (sine wave) generator feeding an amplifier driving a power transformer. The idea is that the power produced is cleaner than the mains power and will spin the motor smoother, also by varying the frequency you can change the speed of the motor, even up to the 78 speed. I don't bother using it with my Ariston turntable.

I have an old Lenco turntable (thrift store purchase) with a 50 Hz motor so it runs fast at 60 Hz, my speed control makes it spin at the correct speed. And yes it does have the 78 speed. Apparently not all 78's are exactly 78 either, many were cut at slightly different speeds, just as different labels used different equalisation!
I did that too. I fed an HP 20 signal generator into a transformer and a phono motor.

Different labels used different speeds before 1928.
Victor started with 70 rpm, then went to 71 and 76 before the standardization at 78.26 by the NAB.
Columbia and Edison used 80 rpm.
Pathe used 90 rpm and 120 rpm.
 
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Anyone have a setup where they can A/B Hafler/DynaQuad and Dolby Pro-Logic decoding (maybe a DVD w/Dolby Surround)?

I videotaped several Dolby Surround encoded TV shows in recent years and listened to them using Dolby Pro-Logic decoding, I also time shifted some movies from my streaming services and listened to them using Hafler/DynaQuad decoding, my casual observation is that Hafler/DynaQuad sounds about as good as Pro-Logic decoding.


Kirk Bayne
I've done it. They are quite close. I used the Hafler diamond.
 
I am new to this thread but truth be known I am really a stereo guy! I see little to be gained in the multi channel mess and ATMOS. I have you guys at a disadvantage as you have not heard Involve decode WITH our SST (Sweet Spot Technology) together, makes 4 speakers go a long way.

I like the view that inside those 2 channels is a hidden surround world if you so chose to extract it, but if you prefer dumb ol stereo good on you.....go for it. The wonderful thing is stereo is compatible to everything and does not need compression and expands out to surround if properly encoded indistinguishable form discrete (see attached study we did years ago.....it really was fair and blind with test monkeys). I think the public is confused as hell about the complexity of ATMOS and who the hell is gonna put all these speakers in a room except if you believe the lie about single speaker ATMOS (poo).

I say we need to go back to the future weather it be Involve encode/ decode or the guys at shadow vector (love that name). If anyone is in doubt just listen to the Suzanne Ciani quad record she did with intelligent Involve triband encode, not my style of music but I still cannot believe how discrete it was in really difficult patched eg pink noise mixed in with gongs and bells n stuff.
One of my reasons is that the phonograph record (not CD4) is still my favorite format. I want my surround on those. The standard CD is second.

I have two movie soundtrack records from 1978 that are supposedly in Dolby Surround with height.
I use a DS and a SQ decoder to decode them (why I want two SMs). So I know it can be done.

Another reason is that I can encode in QS/DS with the equipment I have. I am making recordings in surround.

Discrete is sometimes TOO discrete - puddles of sound at the speakers and nothing else.

And I always want the synthesis ability.
 
Question: why does an encoder need to be triband?
That's an excellent question. The answer is very complicated but it's centered around ensuring the stereo encode does not suffer from image compression as the original QS did. Why compress ( via crosstalk) content with no or minimal surround.

Our encoder also is not a fixed parameter matrix it's a variable matrix that can have a cross talk component variable from 0.15 to 0.42 from memory dependent on the surround content in each band.And controversy the Chucky fact that the maximum separation that we can detect is 12 DB......it caused a lot of research on our part and some other magic numbers.

Again in tests no one can sense image compression in involve stereo. We still have a few encoder evaluation modules for usd$100 I think. The Suzanne Ciani record was made with one of these.
 
On that note, imagine having Involve's Surround Master circuitry included in a receiver or processor... that's the ultimate!
If you’re imto that sort of thing, they make a board that, at least from the specs, looks like it’s basically a SM that you could integrate into the processor of your choice. It’s another bucket list project to incorporate one into my dear old Altec 724.
 
aside:
I was amazed at the apparent channel separation of the QS/RM no logic decoder in my (pawn shop acquired in 1991-11) Pioneer QX-747 quad receiver, the (QS/RM) ABC Command Quadraphonic LP album "The Smoker You Drink..." has great imaging, in my limited experience, second only to discrete (Quadios).


Kirk Bayne
 
I would say it’s a matter of demand vs the additional costs of adding that capability. If only one out of a thousand (or ten-thousand) probable purchasers care about that capability then it isn’t worth it to the manufacturer to include it.
It’s not a conspiracy, it’s just common sense. Would it make sense for someone to start producing record players that can handle wax cylinders?

Actually, in the 1980s, I helped with a project to play cylinders with modern equipment for the IU Archives of Traditional Music.

We had several systems designed to play cylinders.

The first one used a Rabco SL-8 linear-tracking tonearm to play a cylinder that was turned by a cylinder player.

The second one used a Lenco B-55 variable speed turntable to operate a device similar to that pictured that was placed so the turntable can rotate it and the pivoted tonearm could be on top of and play the cylinder.

The third one is diagrammed below. It used a Rabco ST-4 linear tracking arm and turntable to rotate and play a cylinder. We modified the arm.

cylplayer.png


The frame is pivoted in the two lumps at the front. A shaft (front) connects two arms (sides) to move up and down in unison.

They hold the cylinder mandrel shaft horizontally over the turntable.

The rubber drive wheel is clamped to the shaft at a distance from the center of the turntable that turns the cylinder at the correct speed when the turntable is turning at 78 rpm. Cylinders were made in 120, 144, and 160 rpm speeds.

We put a blank disc record on the turntable to have a smooth surface for the drive wheel (instead of the tread on the actual turntable).

The linear-tracking tonearm was modified so it could point up to the top side of the cylinder.
 
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Try finding the front door of the major manufacturers, it does not exist. Its like trying to talk to a politician in Australia, you get the bums rush unless you have a Lobbyist with an orange card costing you a starting $10K a month (we have done that on our other company)
Ahhh. I got anInvolve development kit decoder configured for SQ so I could listen to my SQ vinyl collection through my Sony 3500 receiver using the discrete analogue inputs. Yamaha 500 turntable (inbuilt streamer) connected to aux input input looped out on zone 2 to involve unit then back on multichannel input. Works fine but only if you have multichannel discrete inputs, not on any new amps. Was planning to fit Involve board inside old Sony 2010 decoder case but they are now silly prices and you still need discrete analogue or 2 amps. Now thinking to fit it inside my restored Sony TA1150 amp which has some 4 channel master options and seperable pre and power amp stages. Just to warn you all this is a rabbit hole, but fun. I quite like recording matrix sources to cassette and minidisk, it works just fine but I can hear some graves spinning.
 
Ahhh. I got anInvolve development kit decoder configured for SQ so I could listen to my SQ vinyl collection through my Sony 3500 receiver using the discrete analogue inputs. Yamaha 500 turntable (inbuilt streamer) connected to aux input input looped out on zone 2 to involve unit then back on multichannel input. Works fine but only if you have multichannel discrete inputs, not on any new amps. Was planning to fit Involve board inside old Sony 2010 decoder case but they are now silly prices and you still need discrete analogue or 2 amps. Now thinking to fit it inside my restored Sony TA1150 amp which has some 4 channel master options and seperable pre and power amp stages. Just to warn you all this is a rabbit hole, but fun. I quite like recording matrix sources to cassette and minidisk, it works just fine but I can hear some graves spinning.
I put mine inside a Sony SQD-2010. That, or look for an SQD-2020, keep looking silly prices for sure but you can still find bargains. I posted about it as well as installing the regular (QS) module in my QS-1.
 
In a purely quad context,I will always take discrete over matrix but yes, the matrix decoders are needed to do things with 2 channel records.

Doug
Understood but it frustrates me that when we have done the audience comparison of discrete to Involve encode/ decode on the same synchronised material , instantly switched the majority either preferred Involve or could not hear the difference.
 
From the InvolveAudio Website:
"Involve Decoder Evaluation Kit"
This product is now out of stock. Look out for a design refresh coming in 2023.

Any news about this in Summer 2024?
 
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