EHX Big muff V4 dual op-amp version UA741TC pcb EH1322 (vintage, 1978, made in USA)

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The Electro-Harmonix Big Muff Pi op-amp version, often referred to as the V4, is a vintage American fuzz and distortion pedal originally produced in New York in the late 1970s, here dated to 1978. Unlike earlier Big Muff circuits built around discrete transistors, this version uses dual op-amps, specifically UA741TC chips, mounted on the EH1322 circuit board, which is the defining electronic characteristic of this iteration and gives the pedal its place in the Big Muff family history. Sonically, the op-amp Big Muff is known for a tight, saturated sustain with a pronounced midrange character, a slightly more focused and aggressive voice than the smoother, more scooped transistor versions that preceded it. The three familiar controls, Volume and two independent stages for Sustain and Tone, allow the player to dial in everything from warm, singing lead sustain at moderate settings to thick, wall-of-sound distortion when pushed. It remains particularly well suited to single-note lead lines, heavy rhythm work, and textures where a dense, sustained fuzz character is desired. This is a genuine vintage, made in USA unit, fully tested and serviced, and ready for use both on stage and in the studio. It appeals to players seeking the authentic sound and response of a late-1970s original as well as to collectors of early Electro-Harmonix production. Its large cast-metal enclosure, distinctive graphics, and robust build quality are characteristic of the era in which it was manufactured.