Dear All
I have a ton of background research stuff I read before going nuts to design Involve encode/ decode. Here is one I unearthed from my home desk a few days ago.
I thought this could be a good place to put other similar research/ discussion articles to improve our general pool of knowledge
Enjoy the read, I will ask questions and mark you later.
https://cdn2.imagearchive.com/quadraphonicquad/data/attach/61/61727-Vario-MatrixScan-210420-0003.pdf
Good idea, Chucky, to start a dedicated thread to this instead of so much posted randomly. And I can't begin to tell ya how gratifying it is to see my old article from over forty years ago posted again. I had read so many individual articles, patents, & white papers written about Quad that I wanted to consolidate that into one piece, going from basics to advanced at least for QS..
@par4ken was also a contributor to the MCS Review. He posted a few years back the same article but things get buried fast on QQ so it's good to have in place in this new thread. In fact Ken also posted another favorite article I did called
Uncle Sam's Department of Quad. This was abut all the quad & audio patents I thought would be interesting.
I've liked to think the Survival Guide might have been the basic working knowledge that gave QRXRstore or QuadBob (when he was doing good) their start. Now i find out it might have been useful in the early days of R&D at Involve. How cool is that?
There is an interesting contrast between SQ & QS decoding in the vintage analog mode. SQ always required a basic decoder with quality phase shift networks to begin with. Then logic decoding or Tate DES can be used to enhance the separation. It always seemed to me that each new SQ tech development was just the latest band aid to get it to work right. But of course the Fosgate 101A did sound pretty wonderful. Meanwhile with Sansui's system the decoding and separation enhancement was all done together in what I think is an elegant solution to a tough problem.
Funny story about Sansui & QS... Sansui was not a big name in the audio stores in my area back then. Everything was Kenwood/Pioneer/ Sony SQ. So that's what I went with. I had to actually build a two band QS Vario-Matrix kit from Photolume to be able to hear QS. I was blown away, esp by the stereo to surround effects in the Synthesizer mode.
