Dusk is a digitally controlled analog filter. At its heart is an analog 12dB/Octave low pass filter based around an old-school integrated circuit called an Operational Transconductance Amplifier or OTA. The OTA runs off of split +/-9V rails for great audio quality and a deep filter sound. The digital side brings a whole bunch of convenient and powerful features like controlling the filter setting, tap tempo, MIDI, 6 LFOs, and a platform for all the best filter modes in one small pedal.