SQ: Sony SQD-2020 SQ Decoder

[KevinD9052]

How do the decoders compare between the SQR-4750 & SQD-2020? If I remember correctly, the decoder on the receiver was also Full Wave Matching Logic.

 

[The Bushmaster]

Don't know about the 4750, but I do have a SQR-6750 and it seems to perform as well as the SQD-2020. And yes...Like the SQD-2020 it too has full front/back logic and waveform matching.

 

[KevinD9052]

A 6750! Nice!

 

[Disclord]

One note- the Sony 2010 has full wave-matching logic and f/B Vari-Blend - it doesn't use F/B gain riding logic like the 2020 - I believe the 2070 uses Vari-blend too, but can't remember for sure. It's just a shame that the Vari-blend was only ever applied to the rear channels and not the front too. The Layfette SQ-W also has F/B Vari-blend.

 

[soundcentre]

Having just read the recent posts, the instruction manual to the European English/French/German SQD2010 states and I quote, Circuit system: "SQ decoder with front-back and waveform comparator logic circuits. Regualar matrix decoder."

This is the same description given in the manual for the SQD2020.

The difference is in the use of 4 ICs, 4FETs, 39 Transistors and 47 diodes as opposed to 69 transistors and 84 diodes.

Finally and in terms of sound, the later SQD2010 is superior to the SQD2020 being faster and quieter in operation.

David

 

[Disclord]

Having just read the recent posts, the instruction manual to the European English/French/German SQD2010 states and I quote, Circuit system: "SQ decoder with front-back and waveform comparator logic circuits. Regualar matrix decoder."

This is the same description given in the manual for the SQD2020.

The difference is in the use of 4 ICs, 4FETs, 39 Transistors and 47 diodes as opposed to 69 transistors and 84 diodes.

Finally and in terms of sound, the later SQD2010 is superior to the SQD2020 being faster and quieter in operation.

David

Thanks for correcting me - I told everyone I was an *****, but would they listen? NOOO - it must be to 2070 then that has the F/B Vari-Blend. The 2020 is pretty fast though with the service manual claiming a 3ms attack time. Sony designed and has two patents on Paramatrix selective cancellation type decoders for QS and SQ and its a shame they never produced them.

 

[soundcentre]

Many thanks for your speedy reply, the idea of a Paramatrix is based upon communications technology and if it could have been made at a commercially viable price would have been quite something.

Here in England in the 1970s we did not even get treated to the Sony 4 channel receivers, or tuner-amplifiers as we called them at the time, let alone anything as advanced as a
parallel matrix board!

Best wishes.

David

 

[Disclord]

Many thanks for your speedy reply, the idea of a Paramatrix is based upon communications technology and if it could have been made at a commercially viable price would have been quite something.

Here in England in the 1970s we did not even get treated to the Sony 4 channel receivers, or tuner-amplifiers as we called them at the time, let alone anything as advanced as a
parallel matrix board!

Best wishes.

David

Maybe because I'm sick I don't understand, but what do you mean that the Paramatrix is based on communications technology? Paramatrix is really just CBS's name for a cancellation based decoder instead of the gain riding power transfer wave matching decoding, which can never produce correct results. Only a decoding matrix that changes its structure based on the encoded signal produces correct results. CBS made 5 Paramatrix units but the Tate DES and Shadow Vector performed so much better they abandoned the Paramatrix.

 

[soundcentre]

The reference to communications technology stems from some of the early writing, to try and build a circuit which would deliver the changing structure that you describe.

An analogy was given to the principle of control effected by a reference oscillator in old tube type communications receivers,
which suffered from frequency drift, caused by heat.

In other words if a parallel matrix/parallel logic reference could have been created on a circuit board, it would be the reference to the board dealing with the incoming signal. In lay terms this was promised as being the holy grail to the matrix decoding problems of the early 1970s!

Although promises made were never delivered I have thought that it was this which took Sansui back to the drawing board in the development by R. Itoh of the Sansui variomatrix.

Articles of this nature appeared in the former and late lamented Wireless World in the United Kingdom. The specific principle was, in communications receivers the Wadley Loop or what became known as Phased Locked Loop.

If only the same process of thought could have been applied to SQ technology, but it was not to be, music is far too complex a wave form for voltage logic, let alone that which it seems existed only in dreams!

Best wishes.

David

 

[TPT19764SQ]

Hi everyone and Merry Christmas. My wish for an SQD-2020 came true today. However, I seem to be having some trouble setting it up. I have two receivers a Sherwood-6108 (a surround receiver and a Fisher 4080 (4-channel) and after reading this post carefully about connecting the decoder, I attempted to utilize both receivers as front and rear. The Fisher does well as either a front or rear iwhen connected to auxillary but when it comes to the Sherwood, I don't know either to connect to tape, aux of one of the 6-channel inputs. If anyone can help or have any tips, I'd appreciate them. Other than the connection issue, the SQ decoding is a HUGE difference than the Fisher's odd internal SQ decoder as I've tested the rears with the Intro to the World of SQ Quad LP, Popular Science/Project 3 SQ Test LP, Switched On Bach and Music for Organ, Brass and Percussion by E Power Biggs.

Thanks in advance.


Sent from my iPad using Tapatalk

 

[TPT19764SQ]

Hi everyone and Merry Christmas. My wish for an SQD-2020 came true today. However, I seem to be having some trouble setting it up. I have two receivers a Sherwood-6108 (a surround receiver and a Fisher 4080 (4-channel) and after reading this post carefully about connecting the decoder, I attempted to utilize both receivers as front and rear. The Fisher does well as either a front or rear iwhen connected to auxillary but when it comes to the Sherwood, I don't know either to connect to tape, aux of one of the 6-channel inputs. If anyone can help or have any tips, I'd appreciate them. Other than the connection issue, the SQ decoding is a HUGE difference than the Fisher's odd internal SQ decoder as I've tested the rears with the Intro to the World of SQ Quad LP, Popular Science/Project 3 SQ Test LP, Switched On Bach and Music for Organ, Brass and Percussion by E Power Biggs.

Thanks in advance.


Sent from my iPad using Tapatalk

UPDATE: I connected my ION TTUSB turntable (line in input) as well as my vintage BSR record changer and even though I had to turn up the volume controls, the results turned out good. Still, probably a preamp or etc will do the trick. I'll do more testing and do a review but this is world's away from the SQD-1000 I used to own.

 

[soundcentre]

Your most likely to achieve the desired effect with your two receivers when using tape or auxiliary inputs from the SQD2020. The low output from the decoder to the rear receiver is usually the best one.

Gain can be achieved by increasing the input level to the decoder with reference to the four meters.

I use a pair of Sony TAF8940 stereo amplifiers in the above manner which works fine for me.

Wishing you every success and enjoy your listening experience.

DAVID

 

[rustyandi]

If you like the look of old Quad Decoders then buy them
But if you want to hear the best decoding of QS and SQ and be able to repair the decoder
Get a Surround Master you will not get anything better
Plus they are cheaper as the Aust. dollar has dropped nearly 20pc against the US.dollar
As an old Quad collector I have about 2 thousand SQ and QS lps
I am amazed that any one would buy the old Decoders unless you liked the look

 

[TPT19764SQ]

Okay, here is what I have done after doing some heavy thinking, last night. Since my Ion Turntable has a line in preamp, I connected it to the the SQD-2020 and instead of the front preamp and back output, I took the tape record out jacks and connected it to the discrete aux of my Fisher 4080 receiver since the real purpose was to "replace" the weird SQ decoder on the Fisher treated this as if it were a discrete source. I seem to recall using the SQD-1000 for this purpose with a Panasonic with no issues at all except the non logic of this decoder. For fun, I enjoy listening to the rear channels to hear results coming from records in stereo, SQ, QS, etc. I am overall pleased with the Sony SQD-2020 and will enjoy it until for years and maybe even be luck to land a Surround Master or better, the famous Tate I keep hearing about. Thanks everyone for the replies!

 

[rustyandi]

My point is I have had a Tate Audionics since it first came out
And the QSD1 also
There is no difference between the QSD1 and Surround Master
And if there is any difference between the TATE and Surround Master
When played I cannot hear it or see it on the Scope
It is better than any logic Decoder

 

[Ianf]

Just got an SQD-2020 but very low front channels output in SQ mode, fine in mono, 2-4, and stereo, switches are all nice and clean, rest of controls all appear to work fine, have surround master SQ coming, so this might go on EBay


Sent from my iPhone using Tapatalk

 

[Ianf]

Just got my Surround Sound Master SQ, have to say, best decode I've heard, hearing things in the quad mix I've never heard before. Thanks folks for the recommendation

 

[Tricky X]

Hello all, if anyone has a pdf copy of the owners manual for the SQD-2020, I'd love a copy. I can't find one anywhere online except for those stupid sites that charge you for a copy. Thanks!

 

[Circular Vibes]

http://www.quadraphonic.info/manuals/

Look in the usual spot and there it is! Hope it helps!

Note to Jon, we used to have an easy way to find the links, can that be done again?

 

[The Bushmaster]

Go to hifiengine.com

You'll have to join, but no cost. Go to library, then Sony and way down at the bottom is the SQD 2020 Service manual.

If you need a Operator's manual I have a spare. Send me a self addressed envelop large enough with postage and I'll return it with the extra manual.

PM me