Electro-Harmonix 1978 Op-Amp Vintage V5 Big Muff Pi FX Pedal [Used]

*This is a Used Pedal in our Grade 2 - OK Condition

The 1978 Electro-Harmonix Big Muff V5 is one of the most sought after fuzz pedals ever produced, hailing from the legendary Op-Amp era (1978–1980). This short-lived version of the Big Muff departed from transistor based designs and instead leaned on an integrated circuit (IC) architecture, delivering a sound that is raw, aggressive, and unmistakably massive.

Sonically, the V5 is defined by its abrasive, scooped fuzz character, with a tight low end, biting highs, and a wall-of-sound saturation that cuts through dense mixes. It’s a fuzz that doesn’t politely blend in, it dominates. The addition of the Tone Bypass switch takes things even further, removing the tone stack entirely to unleash a louder, more direct, and mid forward voice that feels immediate and confrontational.

This is the Big Muff sound most famously associated with The Smashing Pumpkins, particularly on Siamese Dream, where its crushing sustain and snarling texture became a defining part of alternative rock history. 

Highly collectible and increasingly hard to find, the 1978 Big Muff V5 is more than just a vintage pedal, it’s a cult classic that represents a pivotal moment in fuzz evolution. For tone hunters looking for authentic op-amp fury with historic weight and unmistakable attitude, this is as real as it gets.

This is a 'used' pedal, in our Grade 2 OK condition, but its an original 1978 version.  It has a lot of signs of usage, scratches and scuffs, no box or manual, but plays and sounds as good as it ever did!