ZIRCON SILICON FUZZ
2
TABLE OF CONTENTS
1
Project Overview
7
Drill Template
2
Introduction & Usage
8
Enclosure Layout
3-4
Parts List
9
Wiring Diagram
5
Build Notes
10
Licensing
6
Schematic
10
Document Revisions
INTRODUCTION
The Zircon Silicon Fuzz is a version of the “Hot Silicon” community project, itself an adaptation of the
Sola Sound Tone Bender for silicon transistors.
The history of this circuit is a bit suspect, with two people claiming originality. It dates to 2003 at the
very latest when Doug Hammond posted a schematic for a circuit he called the Hot Silicon, which was a
hybrid of two earlier circuits from Gus Smalley and Aron Nelson.
However, an almost identical circuit was posted by Mictester in 2009 on freestompboxes.org, and he
claimed he first developed it in the 1970s when he was trying to make a friend’s silicon Tone Bender
from Macari’s (Sola Sound) sound good, and then tweaked the circuit over the following decades until
arriving at the finalized version in 1994. (Sola Sound did make a very small number of Tone Bender Mk
III’s with silicon transistors—these are different than the Jumbo Tone Bender which was basically a Big
Muff clone.)
Maybe it was just parallel development that arrived at the same outcome. Regardless of true origin,
though, the Hot Silicon (or Silicon Tone Bender) is a fantastic circuit that has endured as a classic in the
DIY scene for many years.
The Zircon is a near-direct adaptation of the Hot Silicon circuit, with one change: the input capacitor
switch (called “Fat” in the original schematic) has been changed to a potentiometer so it can be gradually
blended in or out rather than being either full-on or full-off.
USAGE
The Zircon has the following controls:
•
Body
blends between two input capacitors. Note that this may be seen as working backwards, with
more bass on the low end that is gradually removed for a treble emphasis on the high end.
•
Gain
controls the amount of gain in the transistor fuzz stage.
•
Tone
is a Big Muff-style balance control that pans between a low-pass filter (bass emphasis) and a
high-pass filter (treble emphasis).
•
Volume
is the overall output level.
