The Electro-Harmonix Good Vibes Analog Modulator recaptures the iconic chorus/vibrato effect of the 1960s in an updated pedal designed to meet the needs of the modern player. Like the original Uni-Vibe, it uses photocells to create chorus and vibrato with a warm, undulating, liquid-like sound and response that's true to the classic design. Boosted power rails provide 21st century definition and headroom, and an expression pedal input puts free-form control for speed or intensity at your feet. True bypass operation ensures an uncolored signal when the pedal is disengaged.