moog music inc
902 VOLTAGE-CONTROLLED AMPLIFIER:
A universal "variable-gain" black box" with balanced, direct-coupled inputs and outputs. In conjunction with control voltage generators such as the 901, 911, 912, or 955, this instrument will perform virtually any amplitude-varying function.
From "Ultra-Short Form Catalog of Electronic Music Composition Instruments", R.A. Moog Company, October, 1965.