A7

Altec Lansing A7 Voice of the Theatre Loudspeaker System.

1950s–1970s.

Large-format two-way theatre sound reinforcement system developed for cinemas, auditoriums, and live program material.

The A7 combines a front-loaded bass horn and reflex enclosure with a multicellular high-frequency horn system, producing exceptionally high efficiency, strong transient response, and long-throw projection with minimal amplifier power.

The low range employs the 15-inch 416-series woofer mounted within the folded bass horn enclosure, while the high range utilizes the 802-series compression driver coupled to the 511B sectoral horn.

The enclosure integrates both horn-loading and bass reflex principles to extend low-frequency performance while maintaining the immediacy and scale associated with theatre systems of the period.

Originally engineered for commercial motion picture playback, the A7 later became closely associated with recording studios, listening rooms, and early high-efficiency home audio systems.