Vintage Big Muff Pi V1 (1972) – Fully Functional, Professionally Restored (Mechanics Only)

I’m offering a rare Big Muff Pi V1 from 1972, which I received many years ago in extremely rough condition.
The pedal required an extensive restoration—but importantly, this work was strictly mechanical.

The entire electronic circuit remains 100% original and untouched.

What i swapped/Changed: new Poti's , Voltage Supply, 3PTD Knob, LED

Restoration Details

• Original electronics fully intact – no modifications, no component swaps

• All three potentiometers were oxidized beyond repair, so I replaced them with:
• • ~1975 PREH ESA 100k potentiometers (todays cost: 45$ each)
  • Carefully selected as electrically matching pairs
• Due to differences in mounting height, the pots are connected to the PCB via short (~1 cm) wires to avoid stress or damage to the board

• The original footswitch has been replaced with a modern 3PDT switch
• • This allows for true bypass-style operation and LED functionality
  • No changes were made to the actual audio circuit
  • The original footswitch is included if you want to revert it

• A status LED was added using a 1970s-style micro-lamp base with a red cap, mounted inside the enclosure
• • Installed professionally using a screw mount with a stainless steel socket
  • Fully replaceable design
  • Included in the sale:
  • • Original 12V micro incandescent bulb + socket matching the red cap
  • However, to avoid voltage changes, I installed a LED that sits inside the red cap

• The internal 9V battery clip was replaced and adapted to a 9V DC jack
• • Semi-professional work 😉
  • The pedal now runs reliably from a standard power supply (e.g., power plant)
• Original knob caps were missing, (i got one, but it is broke, it will be included), so I installed a set that fits the look nicely
• • Can easily be swapped to your preference

Why the Price is so "Low"

Let’s be fair:
I’ve worked on this pedal. It is no longer 100% original in terms of hardware, even though the sound circuit is completely untouched.

Sound

The sound is absolutely brutal—everything you’d expect from an early Big Muff. It honestly hurts to let this one go.

Why I’m Selling

The honest reason:
I need the money. I recently lost my job, and times are tough. (PS.: Even the price looks like a joke, it's 1000€ :D )

I truly believe this pedal deserves someone who will use and appreciate it more than I currently can.

Demo

there's a little Demo i uploaded for you guys on YouTube - functionality and sound – see link below.