(1986-03) Stereophile mag - 3 Surround Sound Decoders

[kfbkfb]

https://worldradiohistory.com/Archive-All-Audio/Stereophile/80s/Stereophile-1986-03.pdf#page=68^^^
To this end, they have revived the gain-riding decoder--and made it work!


Anyone with an Aphex AVM-8000 decoder and can comment on how well it works?


Kirk Bayne

 

[furui_suterioo]

Given that it is not as good as Tate, I wonder how it would compare to the Lafayette SQ-W(both gain riding SQ decoders).

 

[par4ken]

I disagree with the author that the Fosgate (faster yes) unit is better sounding than the Audionics, I do agree that all the surround channels should be identical though. I also agree with the author about not using a centre speaker. Mid eighties seems late to be releasing a new SQ decoder, however it was designed for Dolby as well. Not as good as a Tate, so why bother?

 

[fizzywiggs41]

They........the Aphex' Decoders were D E S Shadow Vector SQ.

But yes, I agree they were introduced so very late in the quad period 85 to 89 I believe. Where would they obtain SQ source software? At this time there were a few in personal quad collections, but mostly there were an ever dwindling supply.

 

[par4ken]

They........the Aphex' Decoders were D E S Shadow Vector SQ.

But yes, I agree they were introduced so very late in the quad period 85 to 89 I believe. Where would they obtain SQ source software? At this time there were a few in personal quad collections, but mostly there were an ever dwindling supply.

Shadow Vector was the system developed by Lynn Olson of Audionics, nothing to do with Aphex which actually used gain riding (see the article posted). See the very interesting thread here.
Especially interesting are the posts by Lynn Olson!

https://www.quadraphonicquad.com/forums/threads/sq-shadow-vector-soundfield-mapping.25293/
The term DES "Directional Enhancement System" is used in conjunction with Tate.

I suppose that in the eighties there still were many holdouts like us from the seventies that were still interested in SQ hoping for a resurgence and with a large library of encoded material.

 

[fizzywiggs41]

Aphex AVM 6000 from July 1985

 

[fizzywiggs41]

They........the Aphex' Decoders were D E S Shadow Vector SQ.

But yes, I agree they were introduced so very late in the quad period 85 to 89 I believe. Where would they obtain SQ source software? At this time there were a few in personal quad collections, but mostly there were an ever dwindling supply.

Well,....at least the AVM 6000 was . Not certain if the AVM 5000 , or the AVM 8000 were ?

Kinda surprised me too.

 

[kfbkfb]

https://books.google.com/books?id=Y...page&q=tate sq billboard june 22 1974&f=false

Looks like the developers of the Tate SQ decoder used the discrete master tapes to fine tune their logic system, has anyone tried the SQ albums mentioned in this article - EWF and Funny Girl with the SM to see how they decode?


Kirk Bayne

 

[par4ken]

Aphex AVM 6000 from July 1985


View attachment 73886View attachment 73887View attachment 73889

Does Lynn OLson know about that? Shadow Vector was patented by Audionics. I don't know how Aphex got to use it, did they hijack the name?. The magazine article says that Aphex used gain riding logic but limiting separation to something like 10 dB. That doesn't sound like Shadow Vector. Look through the posts in the thread that I posted. A bit of an unsolved mystery! You would think that Audionics would be the one to use Shadow Vector technology!

 

[fizzywiggs41]

Does Lynn OLson know about that? Shadow Vector was patented by Audionics. I don't know how Aphex got to use it, did they hijack the name?. The magazine article says that Aphex used gain riding logic but limiting separation to something like 10 dB. That doesn't sound like Shadow Vector. Look through the posts in the thread that I posted. A bit of an unsolved mystery! You would think that Audionics would be the one to use Shadow Vector technology!

They should , their Dolby Surround Decoder was also reviewed. You can see it sitting just below the Aphex.

 

[fizzywiggs41]

Well Ken, this was1985 and most Decoders /Surround Processor's coming out for the typical audiophile that needed surround for their home theater systems wanted Dolby Surround for film and music videos.
Both Audionics and Fosgate were into Dolby enhancing. Quad (SQ) was a dirty word and no longer considered a viable matrix.
It's really too bad because i think Fosgate/Audionics should have at least offered an SQ OPTION with their various Dolby Surround pro logic units.

 

[par4ken]

Well Ken, this was1985 and most Decoders /Surround Processor's coming out for the typical audiophile that needed surround for their home theater systems wanted Dolby Surround for film and music videos.
Both Audionics and Fosgate were into Dolby enhancing. Quad (SQ) was a dirty word and no longer considered a viable matrix.
It's really too bad because i think Fosgate/Audionics should have at least offered an SQ OPTION with their various Dolby Surround pro logic units.

I still consider Dolby Surround to be a dirty word! I wonder if Audionics was so cash strapped that they allowed Aphex to use the term "Shadow Vector" even though it's not?

 

[fizzywiggs41]

https://worldradiohistory.com/Archive-All-Audio/Stereophile/80s/Stereophile-1986-03.pdf#page=68^^^
To this end, they have revived the gain-riding decoder--and made it work!


Anyone with an Aphex AVM-8000 decoder and can comment on how well it works?


Kirk Bayne

No but it sure would be nice to have an Aphex Decoder.
Either the AVM 5000 , the AVM 6000 , or the AVM 8000 ,provided the price is good. Because I'm a Scrooge.

FWIW : the late great SQ maven Disclord, and well informed QQ member on all things SQ ........( Disclord )praised this DECODER for it's apparent advancements with the SQ matrix.
He never had one but always wanted one to try out and run through some good SQ tests.
For my SQ reading purposes ,he is definitely missed.

 

[fizzywiggs41]

I still consider Dolby Surround to be a dirty word! I wonder if Audionics was so cash strapped that they allowed Aphex to use the term "Shadow Vector" even though it's not?

Perhaps
But as late as in 1990 two Companies offered SQ as an option with their surround and ambience Decoders.

Hitachi and AudioQuest .

 

[furui_suterioo]

Perhaps
But as late as in 1990 two Companies offered SQ as an option with their surround and ambience Decoders.

Hitachi and AudioQuest .

These SQ decoders any good? I don't see much info about them but there is a Hitachi for sale online.

 

[par4ken]

These SQ decoders any good? I don't see much info about them but there is a Hitachi for sale online.

I wouldn't get my hopes up. Burt If you want to, go for it and report back go ahead!

 

[furui_suterioo]

Looking now at the user manuals for the Audiosource models, they doesn't mention anywhere that the "Matrix" button is for SQ, can't find a user manual for the Hitachi.

 

[kfbkfb]

https://worldradiohistory.com/hd2/I...o-IDX/IDX/70s/Audio-1974-08-OCR-Page-0037.pdf
Looks like Hitachi was pro CD-4, this ad doesn't even mention SQ or QS by name, just lumps them into "Matrix".


Kirk Bayne

 

[MidiMagic]

Where's the left side of the bottom page?

And could we see the third decoder?

 

[fizzywiggs41]

These SQ decoders any good? I don't see much info about them but there is a Hitachi for sale online.

My best guess is they provide Basic SQ , after all these are from the end of the 80's decade . More than likely the SQ is an afterthought . Given that by this time Dolby Surround pro logic was preferred by most consumers .