JHS Pedals releases Big Muff 2, a reissue of Bob Myer's unreleased op-amp design
December 20, 2025 · 3 sources
JHS Pedals released the Big Muff 2, a fuzz pedal built from an unreleased Big Muff circuit drawn by Bob Myer, the inventor of the EHX Big Muff. The pedal is listed at $249.00 USD and JHS said in a launch video published December 20 that it is available from the company's website12.
JHS writes that the schematic, a loose sheet labeled "BIG MUFF USING (2 DUAL OP AMPS)," was found in 2021 during a research trip for the book "Made On Earth For Rising Stars: The Electro-Harmonix Story," while digging through materials in Myer's workshop1. JHS describes the drawing as Myer's attempt to reimagine the original transistorized Big Muff circuit using op-amp technology that emerged later in the 1970s, with a different clipping arrangement and an extra gain stage1. Guitar World reports that Myer drew it after EHX founder Mike Matthews requested a Big Muff variant that did not use transistors, and that the design was shelved for five decades3. Guitar World also reports that the Op-Amp Big Muff released in the 1970s was designed by Michael Abrams and Howard Davis, not Myer3.
The pedal has three controls, described by JHS as follows1:
| Control | Function |
|---|---|
| Volume | Controls the output volume. Left is less, right is more. |
| Sustain | Controls the amount of fuzz, which increases the sustain when turned up. Left is less, right is more. |
| Tone | Controls the overall tone. Left is darker, right is brighter. |
Power is 9VDC center negative at 18mA1. Guitar World reports that only 5,700 Big Muff 2 pedals will be made3. JHS describes the result as a collaboration between JHS Pedals, Electro-Harmonix and official EHX archivist Daniel Danger1.
"Where the original Big Muff delivers that iconic "sweet violin-like sustain," Bob's two dual Op-Amp approach pushes into more aggressive, cutting territory."
In the launch video, Josh Scott of JHS said the pedal is "a little bit smoother overall" and "feels just more like an aggressive distortion" than other Big Muffs2. JHS also quotes Matthews, after hearing a prototype, as saying it had "something special" even though it strayed from the traditional Big Muff voicing he typically preferred1.