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Building a Guitar Pedal


The circuit schematic will be as shown in the image (or here

Another more graphical representation:

I wired up the configuration + the smaller components on a prototyping board / perfboard which will lie within the pedal enclosure, along with a 9V battery.

Even though the schematic is relatively simple for a guitar pedal, it was still a bit complicated for me, especially with all the feedback loops! To make sure I got the circuit correct, I printed out a version of the perfboard I used and drew in the circuit manually with pencil.


For the enclosure, I would like to use a metal enclosure for durability. Since the device uses electrical sound as both input and output, the enclosure material will not affect the actual signal processing. I’m thinking about using a Hammond enclosure (

The dimensions of the ZVex Fuzz Factory are 4.70″ x 2.38″ x 1.82″, so I’m thinking of giving myself some leeway by getting an enclosure that is 5.71″ x 3.74″ x 1.93″ (there wasn’t really a better enclosure size given the dimensions of the commercial pedal).

I’ll also plan on decorating the enclosure to some degree. I found this link:, which goes through a few methods of decorating pedals. I will need to decide which method I think looks best while being feasible. (Obviously, some of the more impressive designs and decorations are pretty expensive or inaccessible for DIY.)

As far as how the pieces will be mounted on the enclosure, on the top, there will be five potentiometers / knobs, a push button for power, and an LED to indicate ON/OFF. There will be input and output 1/4″ jacks.

Here is a simple CAD schematic I made; knobs on the top, push button on the bottom, LED in the middle:


  1. Sean Hayes

    These designs and schematics look great. The research into various methods of personalization looks particularly exciting, too!

    (I may have glossed over this, but) Are you purchasing your own circuit board, or constructing your own? If so, what measures are you taking to begin construction? I don’t know anything about how to make a circuit board, so if this is a part of your project, I would love to hear about the process.

  2. Rob

    good grounding/shielding techniques will be important as well to keep noise down. If you have a metal enclosure, that would also help.