Ok so I'm a little young to have been going to Disco's in '79. I was surprised to read this snippet from the year which talks about a Roller Disco event featuring a "holographic" sound system which was comprised of...
"8 x JBL 4343 four way speakers" "Four of them are suspended 20 feet in the air, four are eight feet in the air and all the bass elements are on the ground. There's a computerized processor which randomly throws the sound on any one of the eight suspended speakers"
The Roller disco was in Hawaii but they talk about using this same sound system at the Roseland Ballroom in NYC for a Billboard Disco Event.
http://books.google.com.au/books?id=...0disco&f=false
Also surprised that JBL actually marketed 4343's to be used in discos. I thought these babies were reserved for the studios. check out the brochure
http://www.diyaudio.rs/JBL/JBL%20-%2...0(English).pdf