Rare early first-version run of the V4 op-amp circuit board. Large white board marked EH-3003A/B and pots dating from 1976.
Same make and model Billy Corgan used to great effect on the Smashing Pumpkins landmark album Siamese Dream.
From Kitrae’s Big Muff Page:
The V4 sounds great for crushing, grungy, wall-of-sound distortion, heavy rhythm playing, and heavy leads. Dropped D tuning with humbucking pickups is where this version excels. The V4 fizz or buzz that is typical with a Big Muff has a slightly more machine-like, metallic feel than the transistor versions. Compared to the hint of a revved motorcycle engine underlying the fuzz of the transistor versions, the V4 has more of the hint of a ripping chainsaw underlying the fuzz.
Unlike the transistor versions, the V4 tone is very consistent from unit to unit. Some units may have a noticable volume/gain boost when the pedal is switched off due to the fact that these old Big Muffs do not bypass the signal even when off. The signal still goes through and is amplified by the active op-amps, which can sometimes add a gain boost.