I remember playing with a Halfer set-up in the 70s, connecting a third rear speaker across the positive connections of the L&R channels; made Close to the Edge swirl around the listener in a fun way.

Just received 'Out Among the Stars' by Johnny Cash. Challenging, funny, angry, spiritual all at once; highly recommended.

"Wonderful perfect quadraphonic sound with distortion levels so low as to make a brave man weep" - Prostetnic Vogon Jeltz of the Galactic Hyperspace Planning Council