Fuzz Face Project

Fuzz Face

The fuzz face circuit is probably the most popular circuit for the effect being created back in the 1960's and popularized by rock bands such as The Jimi Hendrix Experience. The effect was one of the first of its kind and lead to the production of countless other circuits that all aim to recreate the same sound. The fuzz circuit is similar to other effects such as overdrive and distortion, except through the fuzz circuits process of amplifying and clipping the original signal, the output becomes a square wave, which will be observed in later parts of this project.

Project Goal

The goal of this project is to reproduce the classic Fuzz Face circuit to the best of my ability and observe the wave forms produced by the output signal. In doing so, the output signal will also be observed for the effects of noise on the circuit by measuring the signal without shielding, and then with shielding.

Circuit Schematic

As shown on the left, the circuit has a lot going on which can be broken up into specific stages. These stages are an input stage, a feedback stage, and an output stage.

This is the PCB used to solder the components

A similar PCB is used to wire the 3PDT switch, the inputs and output jacks, the LED, and the DC power connection to the rest of the circuit.

Enclosure

The enclosure was made using CAD software onshape. The disc shaped enclosure is made to roughly model the original enclosures of the fuzz face. Most guitar pedal enclosures are made of an aluminum casing or some metal to block any signals that could interfere with the signal. The filament used to 3D print this enclosure will not block signals so the inside will be lined with copper tape.

Enclosure loaded into prusa slicer

PCB board with components soldered on

Complete Circuit

Circuit with fully soldered connection between the 3PDT switch PCB board, the fuzz face PCB board, in and out jacks, and the DC connection.

IN vs OUT Characteristics

The following oscilloscope output shows an input test signal sent through the pedal as the orange line. The purple line shows the output which, as shown on the graph, takes on the shape of a square wave due to the saturation of the signal from constant feedback. This is what gives the pedal a crunchy distorted tone.

Low Frequency Guitar Signal

This is the output of a low frequency guitar note. This is produced when the thicker strings of the guitar are plucked, in which they produce notes that are lower in pitch. It should be noted that the oscilliscope is capturing a lot of noise as the circuit was not shielded during this testing.

High Frequency Guitar Signal

This is the output of a high frequency guitar signal. This is produced when the thinner strings of a guitar are plucked prioducing notes that are higher in pitch.

Page updated

Google Sites

Report abuse