'Rainbow Rock' film - possible theatrical quad?

[steelydave]

Came across this poster on eBay recently:


First, does anyone know anything about this film? I can't find any information on it anywhere. There was footage of Billy Cobham at the Rainbow on The Old Grey Whistle Test in 1974, as seen here:

[video=youtube;59lBywfO_yo]http://www.youtube.com/watch?v=59lBywfO_yo[/video]

Obviously the interest to us is that at the bottom there's the mention of the Warner/JVC quadraphonic demo. It doesn't say that the film itself has a quad soundtrack, but it's not out of the realm of possibility is it?

 

[atrocity]

Obviously the interest to us is that at the bottom there's the mention of the Warner/JVC quadraphonic demo. It doesn't say that the film itself has a quad soundtrack, but it's not out of the realm of possibility is it?

It was semi-common for music-oriented films to have four-track magnetic sound, but the layout was usually LCR in front with mono (and frequency-limited) surround. The surround track was also often switched on and off via a 12kHz control tone to prevent the audience from hearing hiss when the track wasn't active.