op amp big muff pi

The 2017 Op-Amp Big Muff Pi is a faithful recreation of the original that features several practical enhancements.

The Electro-Harmonix Big Muff Pi pedals from the 1977–78 period can command big bucks. Compared to other models of the fuzz box, they weren’t made for a long time, so there are comparatively fewer units around.

What makes them different from their sibling Big Muffs is the method by which they produce distortion (to get an idea about how different they sound from each other, check out this video).


The sweet, violin-like sustain of the original Big Muff was made using transistors in four gain stages. That tone inspired countless guitarists, including Jimi Hendrix, who bought one of the first units at Manny’s Music on the now-vanished Music Row of Manhattan’s West 48th Street.

Devotion to the Big Muff would eventually lead Electro-Harmonix to create a range of the devices, including the original, the versatile Big Muff Pi with Tone Wicker, a Deluxe model, the Germanium 4, the Green Russian and the Bass Big Muff Pi, all of which you can check out below. The line also includes recreations with a smaller footprint lie the Little Big Muff and the Nano models – for a comprehensive history of all the models you may want to read this.

Here’s a video that compares the three main Big Muffs for guitar:


But unlike those models, the company’s 1977–78 Big Muffs take a different path to fuzz glory. In a move to reduce manufacturing costs, the pedals from this batch created their distorted tones using operational amplifiers. Commonly known as op-amps, these are tiny high-gain integrated circuits (IC) that produce an output hundreds of thousands of times larger than what’s fed into them. As you might guess, the fuzz they produce doesn’t sound quite like that made with transistors. For that matter, the op-amp Big Muff—sometimes referred to as the IC or V4 Big Muff—featured just three gain stages, rather than four.


As it turned out, these units weren’t very popular, for the simple reason that they didn’t sound like the Big Muff that guitarists had come to know and love. It wasn’t until Smashing Pumpkins guitarist Billy Corgan plugged into one for the group’s breakout 1993 album, Siamese Dream, that guitar players began scrambling to find one of these unloved units.


As a consequence, the original EHX Op-Amp Muffs became hard to find. Realizing this, some boutique manufacturers, from Wren & Cuff to Black Arts Toneworks, started releasing their own emulations of those units – here’s a YouTube playlist of the most popular ones:


[Click on the top left corner to see the list of videos in this playlist]


With original late-70s op-amp Big Muffs now commanding top dollar, Electro-Harmonix founder Mike Matthews decided to reissue the classic pedal at a price players can afford. The new Op-Amp Big Muff Pi is a faithful recreation of the original that features several practical enhancements, including a compact die-cast chassis and true-bypass switching.

Best of all, Billy Corgan himself says it’s as good as the original op-amp Big Muff. “The magic’s still in the box,” he says. “I can still get what I’m looking for!”

The pedal has also won kudos from Big Muff collector and historian Kit Rae, who says it delivers “a huge, crushing Big Muff sound with more crunch… great for grungy, wall-of-sound distortion, heavy rhythm playing and heavy leads.”

The Op-Amp Big Muff Pi features:
– A faithful reissue of the original classic circa 1978
– Controls for Tone, Sustain and Volume, plus a Tone Bypass switch
– True-bypass switching for maximum signal integrity in bypass mode
– A rugged, compact, die-cast package measuring (in inches) 2.75 (w) x 4.5 (l) x 2.1 (h)
– A low street price of $80.60

The pedal ships with a 9-volt battery and accepts the optional EHX9.6DC-200 AC Adapter.

Give it a listen below as Corgan takes his first look at the Op-Amp Big Muff Pi.

Here’s a video demo that compares by Chicago Music Exchange that compares the (bassier and smoother) Russian Big Muffs with the Op-Amp reissue. – Christopher Scapelliti