1978 Electro-Harmonix Big Muff Pi V5 (Op Amp Tone Bypass)

..with the famous bottom-mounted "factory-modded" large green Mylar capacitor that establishes this unit is from the very first, historic production run of the V5 in 1978. (full details are below).

Condition is FAIR because, as you can see, it's kind of beat up on the outside; so, if cosmetic condition is important to you, move on and spend a bunch more $.

If, on the other hand, it's TONE over LOOKS for you, then stick around and get a better deal on this old classic!

This pedal sounds AMAZING!! and is everything I've ever wanted in a Big Muff Pi...a true classic!!! (I'm just not playing out that much anymore and I have bills to pay).

Comes with a correct power adapter.

Here's the story on the big green, bottom-mounted capacitor:

What you are looking at is one of the most famous production quirks of 1978 Electro-Harmonix history. Having that large green Mylar capacitor (and often two accompanying resistors) soldered directly onto the solder/trace side (the bottom) of the board—facing down toward the bottom backplate—is exactly how Electro-Harmonix built the V5 Tone Bypass circuit.

The Story Behind the Bottom-Mounted Cap:

This specific layout happened because of a classic, fast-paced manufacturing shortcut:

• Leftover Circuit Boards: Electro-Harmonix had an enormous stock of printed circuit boards printed for the Version 4 non-bypass op-amp layout (the EH-1322 board).

• The Last-Minute Mod: When founder Mike Matthews decided to aggressively push out the new Version 5 with the "Tone Bypass" switch feature, the company didn't want to throw away thousands of perfectly good V4 circuit boards.

• The Factory Hack: To adapt the old boards for the new switch feature, factory workers manually hand-soldered the tone bypass capacitor and two resistors directly onto the back traces of the PCB during final assembly.

This means your unit is from the highly desirable first production run of the V5 circuit, featuring the authentic "trace-side" factory modification. If that capacitor were cleanly mounted on top of the board with everything else, it would actually indicate a much later, re-designed production run. Your pedal's quirky bottom-mounted "greenie" confirms its exact 1978 pedigree.