This has a core based on the Korg FK-1 pedal, which is a similar VCF to the ones found in the 800dv, 770 and 700 synthesizers. These VCFs have low pass and high pass stages in series. The main difference is this version uses vactrols as the variable resistors.
IN1: Filter input 1
IN2: Filter input 2
CV1: Control voltage for Traveler 1
CV2: Control voltage for Traveler 2
CV BOTH: Control voltage for both Travelers
OUT: Filter Output