Electro Harmonix Big Muff Pi 2 Distortion/Sustainer Pedal

The Big Muff Pi 2 is a dual op-amp fuzz pedal born from a rediscovered 1970s circuit design by Electro-Harmonix's Bob Myer. Josh Scott of JHS Pedals decoded Myer's original hand-drawn schematic and brought this forgotten topology to life. The result sits apart from the classic Big Muff Pi whilst maintaining the core sonic DNA–a slightly fuzzier, more dynamic character with a crispy top end and booming low response that appeals to fuzz enthusiasts seeking something beyond the standard formula.

Housed in a compact nano die-cast chassis measuring 4.5 x 2.75 x 2.1 inches, the pedal employs three intuitive controls. The Sustain knob governs distortion range from medium grit to full fuzz intensity; the Tone control spans brash treble to deep bass via a high-pass sweep; Volume sets overall output level. True bypass switching with silent relay engagement comes standard, plus a first for Big Muff designs–momentary footswitch action accessible by holding the switch for half a second or longer. Power delivery via 9V battery draws only 15mA, or use an optional centre-negative 9.6VDC adapter (200mA maximum, 12VDC ceiling).

The circuit employs two Dual Op-Amps configured for a unique gain structure that sits between refined and wild. Input impedance measures 117kΩ; output impedance maxes at 2.7kΩ, ensuring solid interface with typical amplifier inputs. Status LED illuminates when engaged, providing visual feedback during live performance. Momentary action can be disabled if preferred, allowing straightforward latching bypass behaviour.

Features

• Dual op-amp fuzz circuit design rediscovered and engineered from original 1970s schematics
• Nano sized die-cast chassis, 4.5 x 2.75 x 2.1 inches, compact pedalboard footprint
• True bypass with silent relay switching and latching or momentary footswitch modes
• Three-control layout: Sustain, Tone, and Volume for intuitive real-time adjustment
• Input impedance 117kΩ, output impedance maximum 2.7kΩ for clean signal interfacing
• Power via 9V battery included or optional 9.6VDC centre-negative adapter, 15mA draw
• Status LED illuminates effect engagement; momentary action toggle disableable via internal switch
• Input and output jacks positioned right and left sides respectively for flexible cable routing