Voice of the Theatre speaker systems (1945 - ?)
Range of classic two-way speaker systems, originally designed for cinema sound, later becoming popular for general live reinforcement. The design was the result of a collaboration between John Hilliard and Jim Lansing (who went on to leave Altec-Lansing and form JBL (his initials)).
The efficiency of the designs provided high sound pressure levels from the limited amplifier power available at the time.
A-4 (1945) The most-often used Voice of the Theatre system, with many still in use in cinemas today.
A-7 (1966) Designed for smaller venues - relaunced as the Legacy A-7 in 2003
AudioWorld article about the relaunch
A-8 (1966) Designed for smaller venues
More information: http://www.ominous-valve.com/altec.html