Big Muff Pi

The Big Muff Pi (π), often known simply as the Big Muff, is a fuzzbox produced in New York City by the Electro-Harmonix company, along with their Russian sister company Sovtek, primarily for use with the electric guitar. It is used by bassists as well due to the Big Muff's low-end frequency response.

The following is a direct quote from Mike Matthews, Electro-Harmonix founder and president:

"Back in 1969 I (Electro-Harmonix) was already selling the Muff Fuzz, which was a mild overdrive circuit in an LPB-1 box. I wanted to come out with a three knob distortion unit in a bigger box. I asked my buddy, Bell Labs designer, Bob Myer, to design a unit, one that would have a lot of sustain. When I got the prototype from Bob, I loved the long sustain. This was done by cascading the circuit into additional sections, each one clipped by twin diodes. However, when you clip, the tone can be a bit raspy. So, I spent a couple of days changing capacitors to roll off distortion in the highs, and eventually found that the best long sustaining tone that was a sweet violin like sound was done by having three capacitors in different parts of the circuit rolling off the rasp. We plunged into production and I brought the very first units up to Henry, the boss at Manny's Music Store on 48th Street, NYC. About a week later, I stopped by Manny's to buy some cables, and Henry yelled out to me, 'Hey Mike, I sold one of those new Big Muffs to Jimi Hendrix.' "

An earlier Electro-Harmonix pedal, the Axis Fuzz, was also manufactured for the Guild guitar company as the Foxey Lady and used a similar chassis as the early Big Muffs, but had a simpler two-transistor circuit. With the introduction of the Big Muff the Axis was discontinued and the Foxey Lady pedal became a rebranded Big Muff. It was available at least until the mid-1970s.

The Big Muff Pi was the first overwhelming success for Electro-Harmonix's line of pedals. Due to its reliability, its low price and its distinctive sound, the Big Muff sold consistently through the 1970s and was found in innumerable guitarists' pedal collections. For example, David Gilmour and Carlos Santana (although Santana owned one it is reported he did not use it) were some of first famous users of the pedal. David Gilmour famously used the Big Muff on the Pink Floyd albums Animals and The Wall and most recently on his 2006 On An Island tour. Other artists who used the Big Muff during the 1970s include Thin Lizzy, Kiss, Frank Zappa (though Zappa had it modified to produce a very non-typical Big Muff distortion), and Ronnie Montrose. Even after the Electro-Harmonix company was forced out of business in 1982, the pedal remained in such demand that clones of the Big Muff were made by both competing corporations and independent pedal builders, and demand for "vintage Big Muffs" rose. Unsurprisingly, when Matthews restarted Electro-Harmonix in the 1990s, the Big Muff was one of the first pedals he reintroduced to the market.

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