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Based On
Tone Bender Mk. II
Effect Type
Build Difficulty
Deimos printed circuit board

Printed Circuit Board

What's included?
PCB, build instructions, and parts list.


In stock

Complete Kit

Not yet available.
Kits are developed based on interest, so if you’d like to see one for this project, let us know.

Project overview

The Deimos Germanium Fuzz is a clone of the Sola Sound Tone Bender Mk. II (two-knob) that was produced and sold by Macaris in London beginning in late 1966. It was one of the pioneers of guitar effects pedals, hugely influential both musically and electronically to everything that followed.

While the previous version of the Tonebender was essentially the same circuit as the Fuzz Face, the Mark II version added a single-transistor boost/buffer stage in front of it, increasing the drive level but also making it play nicer with effects that come before it.

The Deimos project is a faithful reproduction of the Tone Bender Professional Mk. II with one big enhancement: a voltage inverter has been added which allows it to be powered with a standard center-negative adapter while maintaining the positive-ground operation of the original. The PCB also includes trim pots so you can dial in a perfect bias without having to swap out resistors.

In addition, the 125B update of the Deimos adds a toggle switch allowing you to bypass the first transistor stage to convert it into the previous version of the Tone Bender, often referred to as the “1.5”. (There is one other capacitor that had a different value in the 1.5 circuit, but it has very little impact on the sound.)

Documentation & Build Reports

Project Documents