The original Russian ICs K140UD12 are used in the sound circuit. We made several updates to adapt the VCF for modern modular synth requirements, including independently buffered inputs, an extended Cutoff knob, elimination of clicks when switching filter modes, and an added output stage to prevent signal inversion. The result is a much punchier bass sound and very smooth controls.

Technical specifications:

Input level - up to 20V peak-to-peak

CV input level - -10V to +10V

Filter modes - BP (6dB/oct) / LP (12dB/oct)

Power consumption - +11mA, -11mA

Module width - 10 HP

Module depth - 25mm

More information - Erica Synths