The Erica Synths Black DJ VCF provides sound treatment functionality typically found on DJ decks – it is fully open when the cutoff knob is set to 12:00; when turned counter-clockwise, lowpass filtering is applied and when turned clockwise, highpass filtering is applied topped with nice-sounding resonance. This module provides hands-on control over the sound during performance, as well as unconventional timbre modulations that are hard to achieve with conventional state variable filters. The Black DJ VCF is of a fully analogue design and consists of two VCFs – highpass and lowpass in series and the filter management is done by complex CV routing.