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Quick Hit: Electro-Harmonix Op-Amp Big Muff

Quick Hit: Electro-Harmonix Op-Amp Big Muff

The black sheep of the Big Muff family returns—as brash and beastly as ever.



Unique, high-mid forward Big Muff tones. Cuts through sonic clutter. Relatively even distortion spectrum. Affordable.

Some Muff fans may miss fat low end. Highest gain levels can sound thin.


Electro-Harmonix Op-Amp Big Muff


Ease of Use:



Within the expansive Electro-Harmonix Big Muff family, the Op-Amp Big Muff is a true black sheep. Because for all the tone differences that exist between, say, a first-generation triangle Muff and and a bubble font Sovtek, they share a common four-stage silicon transistor architecture. The original Op-Amp Muff from 1978 dispensed with all that—substituting Op-Amps for the four transistors. It was a short-lived experiment that resulted in a very different tone signature—different enough that some Muff purists don’t consider it a real Muff at all.

The new Op-Amp Big Muff captures those sonic differences with admirable authenticity. It’s buzzier, fizzier, and more high-mid forward than transistor Big Muffs. And when A/B’d alongside an original Sovtek (the bassiest Big Muff of all), it can even sound relatively thin. Make no mistake though, through a loud amp with a 12" speaker (or four), the Op-Amp is a beast—capable of grinding, present, wide-spectrum distortion that cuts through sonic clutter more effectively than any Muff I’ve ever played. And for guitarists wishing to counteract the boomier aspects of Big Muff tone with mid-boost controls, the Op-Amp Big Muff might be the real fix they’re seeking.

Test Gear: Fender Telecaster Deluxe with Curtis Novak Widerange humbuckers, Fender Jazzmaster, ’68 Fender Bassman, ZT Lee Ranaldo Club