Like the legendary Big Muff Pi of the '70s, the Electro-Harmonix Big Muff Pi reissue has three controls that let the player dial in the finest harmonic distortion/sustain ever produced. The Big Muff Pi's Volume control adjusts the output level. The Sustain control optimizes the long sustain with just the right amount of harmonic distortion, and the Big Muff Pi's Tone control provides a range of sounds, from warm bass to crisp treble. From Pink Floyd to the Chemical Brothers to Korn, everyone wants a piece of the Pi!