quadraphonic

The package, overseen by Yoko Ono, contains raw studio mixes, remastered quadraphonic mixes, demos, a documentary, a 120-page book and more.

All he needs is the rhythm — in this case, voluminous quadraphonic sound set in four corners of an active room.

Short solo cello fragments are recorded and played back through quadraphonic speakers.

A stage technician at the Birmingham Odeon remembers rigging a quadraphonic sound system to replicate a helicopter swirling around the auditorium, which has since become a cinema.

In full effect, the quadraphonic sound in this cavernous space is a triumph of engineering, and a feast for the ears.