The Electro-Harmonix Big Muff Pi is one of the most famous, heavily cloned, and historically significant fuzz/distortion pedals ever created. Introduced in 1969 by Mike Matthews, the Big Muff is defined by its massive, singing, violin-like sustain and its heavily scooped mid-range.
Every classic Big Muff utilizes a straightforward three-knob layout that offers a surprisingly wide palette of saturated textures:
