From Dr. Scientist:  

Dusk is a digitally controlled analog filter. At its heart is an analog 24dB/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.

• 3 Filter Modes, 6 LFO Waveforms in a small form factor
• High quality analog signal path
• Premium parts and components throughout
• True Bypass with soft touch relay switching
• MIDI implementation of all digital controls
• Expression pedal/CV control over Filter Cutoff
• Top mounted audio and power jacks
• Designed and handmade in B.C., Canada
• Mono input, Mono output, TRS Expression input/TS Control Voltage input
• Filter Control: +/-24dB analog, resonant low pass filter
• Exp Input: TRS cable, any resistance
• All analog signal path
• Dimensions: 70mm wide, 129mm long, 59mm tall (2.75” wide, 5.1” long, 2.3” tall)