OT Quadraphonic audio media - test-drb@ccmp.vtda.org

22 Feb 2002

...
  There were three competing systems: QS (Sansui), SQ
(Sony) and CD-4
 (JVC).  Only the CD-4, which used a supersonic subcarrier a la FM
 broadcasting, required a special stylus on the cartridge (Shibata).   
I bought and assembled the Southwest Technical Products CD-4
decoder, but could never get it operational (SWTP == on-topic).

If anyone on the list knows of anyone with experience
with this decoder, I'd appreciate a pointer in their
direction...