I investigated this album (Beck, Bogert & Appice - Live) about as much as you can do for an album only released in Japan, and came to the conclusion that it was stereo only. CBS/Sony Japan were the patent and copyright holders for the SQ system, so they had a vested interest in supporting and promoting it, and all the other Japan-exclusive live albums that the label did (Andy Williams An Evening With, Mountain Twin Peaks, Santana Lotus, Percy Faith Live, Michel Legrand Live in Japan, Sergio Mendes & Brazil '77 Live, and several others) made no attempt to hide that they were SQ-encoded, with the logo on the front and back cover, and also on the labels like all the other CBS/Sony SQ quad releases. I think the BBA Live album was just a smidge too early (mid-'73) as most of those other Japanese live quad releases are from later in the year or in 1974 before CBS/Sony Japan gave up on pop quad releases altogether.