PARTICLE VINTAGE FUZZ
2
TABLE OF CONTENTS
1
Project Overview
6
Drill Template
2
Introduction & Usage
7
Enclosure Layout
3
Parts List
8
Wiring Diagram
4
Build Notes
9
Licensing
5
Schematic
9
Document Revisions
INTRODUCTION
The Particle Germanium Fuzz is an adaptation of the Interfax HP-1 Harmonic Percolator, an extremely
rare and highly sought-after fuzz/overdrive from the mid-1970s. Not much is known about the history of
the unit other than that they were made in Milwaukee, Wisconsin by Ed Geise, owner of an electronics
repair shop called Interfax Electronics.
The Harmonic Percolator is a two-transistor fuzz, but it bears no resemblance to any other of its
contemporary pedals such as the Fuzz Face or any of the Tone Bender variants. It uses a PNP germanium
transistor paired with an NPN silicon, allowing it to run in a standard negative-ground configuration.
The transistors and some of the components were gooped or obscured in the original. To add the
mystery, there were several circuit changes made throughout the run, so even if you manage to find one,
there’s no guarantee that it’s one of the “good” ones.
The Particle is an exact replica of the known schematics of the Harmonic Percolator, but with one
addition. The Harmonic Percolator uses clipping diodes (unlike most germanium fuzzes) and so as with
other Aion FX projects, we’ve added a diode switch to go between two different sets of diodes, or to
disengage the diodes entirely.
The Harmonic Percolator was also the basis for the Catalinbread Karma Suture, which is available in
both germanium and all-silicon versions. The Karma Suture was
.
USAGE
The Particle has the following controls:
•
Harmonics
controls the signal level coming into the transistor fuzz stage. Its effect is nearly
identical to rolling back the guitar volume.
•
Balance
is an output volume control.
•
Diodes
selects between three sets of clipping diodes.
