The DOD Compressor 280 employs an electro-optical circuit that varies the pedal’s dynamic compression using a light-dependent resistor and internal LED. At lower settings, its Compression knob adds a subtle volume-leveling effect that adds a touch of evenness to the guitar’s signal, raising the level of low-volume playing and limiting the maximum volume of harder-hit single-note passages and chords. At higher settings, the Comp “squashes” the initial attack and raises the level of notes and chords as they decay. The Level knob controls overall volume of the signal and can act as a boost if desired. Its true-bypass wiring allows a guitar’s tone to remain pristine when the box is disengaged, and its modern power supply makes it more pedalboard-friendly. Visit www.dod.com.