Tanglewood, the performing arts space in Massachusetts which is the home of the Boston Symphony Orchestra, apparently made quadraphonic recordings of their shows in the 1970s and sent them out to radio stations for broadcast. They had the capability to make matrixed and discrete tapes. I mention this in case anyone ever comes across a tape of a show from Tanglewood from that time frame.
Source for this info: http://www.americanradiohistory.com/Archive-Modern-Recording/70s/Modern-Recording-1976-08-09.pdf (page 36)
Source for this info: http://www.americanradiohistory.com/Archive-Modern-Recording/70s/Modern-Recording-1976-08-09.pdf (page 36)
