According to Feldman, he was contacted by Fixler, who had come up with something independent of Scheiber. Fixler's was intended for Quad headphones, but proved to work great with speakers. The two of them worked together, adjusting the parameters in real-time, the encoder going straight into the decoder while they listened and tweaked it!
They sold it to EV, but the final parameters took into account things like mono-mixdown compatibility, after being fed into a computer for the final equations EV used. What kind of computer EV supposedly had access to in 1970 I do not know lol.
Also significant to me is that Scheiber's was concieved from the beginning to incorporate logic, while EV was intended to work correctly without the expense.
I don't know why, but retro-fitting an EV decoder with logic seems extremely cool to me. I guess you'd have to see the sound distribution illustrations in Feldman's book to appreciate just how evil SQ and QS really are. Note that Feldman does NOT present them that way himself. It was a decade before "stereo image expanders" used phase relationships to affect apparent separation, and neither CBS nor Sansui had any idea what a mathematical abomination their systems really were. You could use a stereo image expander to compensate for the reduced seperation in EV or Dynaco, but in SQ or QS it would just make everything a whole lot worse. The Tate is so great because it uses logic to kill crosstalk by injecting reverse phase signals into other channels, but with EV or Dynaco or any other amplitude matrix, a stereo image expander would do the exact same thing without logic, because there are no whacky assymetrical phase angles like with the other two.
So say a Left Front signal has a 20% bleedover into the Right Front. No problem, just have a fixed setting to inject that exact amount out of phase into that channel, no logic necessary.
I can't wait to try this