What kind of sound does the Electro-Harmonix Op-amp Big Muff Pi Fuzz Pedal produce?

The Op-amp Big Muff Pi delivers the iconic, thick, and creamy fuzz tones popularized in the '90s, famously heard on albums like Smashing Pumpkins' Siamese Dream. Its unique op-amp circuit provides a distinct, aggressive character with massive sustain and a powerful low end, setting it apart from traditional transistor-based Big Muffs. It's perfect for huge, wall-of-sound distortion.

How do the controls on the Op-amp Big Muff Pi Fuzz work?

This pedal features three main knobs: Volume adjusts the overall output level, Sustain controls the amount of fuzz and sustain, and Tone shapes the frequency response from dark to bright. Additionally, a Tone switch allows you to bypass the tone circuit entirely, providing a full-range, uncolored fuzz sound with even more output and presence.

Who is the Electro-Harmonix Op-amp Big Muff Pi Fuzz for?

The Op-amp Big Muff Pi is ideal for guitarists and bassists seeking the legendary '90s grunge and alternative rock fuzz sound. Its massive sustain and unique tonal character also make it a great choice for players exploring heavy shoegaze, doom metal, or anyone wanting a distinct, powerful fuzz that stands out in a mix.

What are the power requirements for the Op-amp Big Muff Pi Fuzz?

The Op-amp Big Muff Pi can be powered by a single 9V battery. For continuous use or integration into a pedalboard, it also accepts a standard 9V DC power supply (sold separately).

Does the Op-amp Big Muff Pi Fuzz affect my tone when it's off?

No, the Op-amp Big Muff Pi features true bypass switching. This means that when the pedal is disengaged, your instrument's signal passes directly through without any electronic interference from the pedal's circuit. This ensures your clean tone remains pure and unaffected, preserving your guitar's natural sound.

Electro-Harmonix Op-amp Big Muff Pi Fuzz Pedal

Name: Op-amp Big Muff Pi Fuzz Pedal
Brand: Electro-Harmonix
Rating: 4.5 (66 reviews)

Op-amp Fuzz Pedal with True Bypass Switching and Tone Bypass Toggle

Item ID: OpAmpBigMuff

Electro-Harmonix Op-amp Big Muff Pi Fuzz Pedal

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listed for $75.00

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Billy's Famed Muff Fuzz Tone in a Compact Pedal

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Billy Corgan and James Iha (Smashing Pumpkins) built an empire on Siamese Dream's distinct brand of psychedelia-meets-rock-alternative. A key ingredient to this record's iconic sound, as guitarists today know, is Billy's famed late-'70s V4 IC Big Muff. Now, Corgan and EHX have carefully bottled the tone and response of the original in the Electro-Harmonix Op-Amp Big Muff Pi. This pedal faithfully captures the fuzz-laden and explosive textures of Billy's op-amp equipped '70s Muff. Controls for Volume, Tone, and Sustain (gain) make it quick to dial in the textures your music demands. Meanwhile, a tone bypass toggle temporarily bypasses the pedal's tone circuit for maximum output and aggression. The new compact size and die-cast durability preserve the Siamese Dream tone for a new generation of fuzz fans.

Based on the late-'70s op-amp Muff

Earlier transistor-loaded Muffs are regarded for their smoother bite and more controlled sustain. Yet a key ingredient in Corgan's Siamese Dream tone was the op-amp-loaded, late-'70s Big Muff Pi. The EHX Op-Amp Muff captures the grit and gain of Corgan's classic in a compact new pedalboard-friendly footprint.

Plenty of sweet spots in these pots

Corgan's Siamese Dream tone was rarely a single full-range performance, but more commonly, the stacking of 5, 10, or 20 guitar parts at varying stages of gain and contour. The EHX Op-Amp Big Muff Pi affords limitless options for tone stacking, from hot snarling leads to plaintive, lingering pedal-point drones. A feature that Sweetwater reviewers particularly enjoyed was the tone bypass switch, which temporarily bypasses your settings for bursts of raw power.