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Octahedron Octave Fuzz

Based On
Roger Mayer Octavia
Effect Type
Octave fuzz
Build Difficulty
Project Summary
An all-transistor redesign of the fuzz effect made famous by Jimi Hendrix, which adds an octave-up overtone to the harmonics.
Octahedron Octave Fuzz printed circuit board

Printed Circuit Board

What's included?
PCB only. Build instructions and parts list can be viewed or downloaded from this page.


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 Octahedron Octave Fuzz is based on the Mayer Octavia, a transistor-based octave fuzz pedal originally designed in 1970 as an overhaul of the transformer version.

The circuit was designed by Roger Mayer who had built all of Jimi Hendrix’s octave units going back to 1967. The original used a transformer as the phase splitter, and underwent many iterations between 1967 and 1969, with Roger making tweaks and Jimi providing feedback, often after playing it live. The transformer Octavia was never sold commercially, so there was no final or standard version of the circuit.

Roger Mayer was never satisfied with any of the transformer versions and by 1970 he had redesigned the circuit to use all silicon transistors with no transformer. Jimi did play one of these new versions before his passing, but it has not been linked with any actual recordings.

The transistor Octavia was finally released commercially in 1980 in the distinctive “space ship” enclosure. Roger has produced versions of the transistor Octavia ever since, but he has never revisited the transformer version because he felt it was inferior.

In 2003, Roger released an updated version called the Vision Octavia, which used a more modern enclosure design and also added a passive treble-cut tone control that can reduce the harshness of the octave.

The Octahedron project is based on the Vision edition with the tone control, although the control can be omitted if you’d prefer to build the stock version. We have also included a switch to disable the octave-up effect and turn it into a more typical fuzz.

The two Octavias don’t have much in common and don’t sound alike, but both are worth building if you like octave fuzz. The transformer Octavia is available as our Octagon project.