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Building a Guitar Pedal



I will be making my own guitar pedal based on the Zvex Fuzz Factory (  The Fuzz Factory is a fuzzbox, which is used to make a distorted, fuzzy effect to the signal from an electric guitar. The pedal provides a type of distortion by clipping the clean signal, adding various overtones and sustain.


I play guitar in my spare time and record my own music. However, I’ve never actually purchased actual guitar pedal hardware, so I thought it would be fun and practical to build my own! In addition, along the way I’ll learn what’s going on under the hood in pedals that make a “fuzzy” effect. It definitely helps that the Fuzz Factory schematic is readily available online and seems to be the perfect scope for a final project.

Background Research

I found a sample schematic of the Fuzz Factory:

Another representation that’s a bit more pictorial:

According the Zvex, the manufacturer of the Fuzz Factory: “Although the five knobs are named for the parameters over which they seem to have the most control, please don’t hold me to it.”

  • Volume: output level
  • Gate: sets a floor for output sound
  • Compression: reduces loud sounds and amplifies low sounds
  • Drive: increases distortion
  • Stability: changes supply voltage

The pedal is popular with rock musicians; see Plug In Baby by Muse:

With these as guidelines, I will construct / solder up the circuit and place it within an enclosure, just like a commercial pedal!


  1. spectore

    What are “comp” and “stab”? In class we talked about volume, drive, and a bit about gate I think, so I have an idea of how those elements can be altered from their original state, but what is happening under the hood to change “comp” and “stab”? What does that sound like?

  2. Sean Hayes

    This seems like an awesome project.

    I would be curious to see a diagram of the enclosure/housing you plan to create – do you intend to use metals for the housing? How would you alter the visual appearance of the original, either in layout or in aesthetic appearance?

    Something else that the Fuzz Factory company totes is it’s ‘hand painted pedals’, it would be awesome to see how you plan to ornament/personalize the exterior and continue the legacy!

  3. Rob

    If you are interested in learning about some circuit analysis tools, seems like this is a great candidate for using SPICE. For example, check out: