The HN VCF features high-pass and low-pass channels with a slope of 12 dB per octave as well as a 6 dB band-pass. Cutoff, resonance and drive section can be adjusted via the inner parts of the module's concentric potentiometers. The outer knobs allow bipolar attenuation of control voltages, which can be fed to the circuit via dedicated inputs. Additionally, there is a 1v/octave connector, making it possible to play the filter tonally while self-oscillating. The fourth output of the HN VCF is named “LP!”. Here, results of an 18 dB per octave low-pass can be tapped off. The exclamation mark signals, that the drive circuit works more fiercely in this channel.