Valley International Dynamite

This is a good all-around multifunction utility dynamics processor with simple controls you can quickly navigate and stereo-linkable channels.

It can be used as a compressor, limiter, gate, expander, ducker or de-esser, with a key input available for all functions. The control voltage and VCA input are patchable, so you can use an external voltage source to modulate the VCA as a tremolo or envelope follower, and the detector circuit control voltage can be used to link other VCAs to track envelopes, control pitch on VCOs, sweep VCFs or other synth module functions. Extremely versatile.