AS3320D

The ALFA AS3320 (SOIC-18) is a high performance voltage-controlled four-pole filter modelled after the CEM3320, with on-chip voltage-controllable resonance. The chip can be configured as an lowpass, highpass, bandpass, or all pass filter. It has an exponential (V/Oct) frequency control input which can cover more than ten octaves with little control voltage feedthrough. The Resonance CV allows control of the resonance from zero to low distortion oscillation. For more demanding applications, further trimming can improve control voltage rejection. Each filter section is fully temperature compensated and has consequent low warm-up drift.

This chip can be used to build any filter circuit based on the CEM3320 VCF chip. The 3320 was used in classic instruments like the Sequential Prophet 5 and Pro-One mono synth, the Elka Synthex, the PPG Wave 2, and even in the Fairlight CMI and the LinnDrum!