This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.

Tuesday, August 4, 2015

Dunlop Fuzz Face - Eric Johnson

Here's a layout for the Eric Johnson Fuzz Face. Had someone ask if they could build it on the basic Fuzz Face layout from last year. Since there's a few extra components in the EJ version, I thought I'd make a specific layout for it. Should still fit in a 1590a though. Q1 is a BC183 (hfe ~250), and Q2 is a BC183C (hfe ~650). Use the trimmer to bias Q2 to 3v.


  1. Hi man, the diode protection this backwards in the layout.wrong polarity.And the 1uf cap in others layout is NP, not electrolitic.Tomorrow say if it works.thanks!

  2. Replies
    1. Thanks for verifying. Fixed the diode polarity. The polarized cap shouldn't matter much at all tonally. And it's oriented the right way if you do use a polarized cap. I'm just assuming most people have more polarized electros than non-polarized ones.

  3. I'm new to this forum
    I built this fuzz, when I plug it in , bypass works fine but when I click on effect I get a drop in volume and barely any fuzz .. can only get trimpot voltage down to 4.75v
    Can anyone suggest what may be going wrong.
    I'm a complete Nube

    1. Trying using a larger value trimmer. You may also need to adjust the 39k resistor going to the collector of Q1/base of Q2.

  4. Yeah cheers I fixed that problem. Q1 transistor needed to be
    now everything working however I’m now getting a
    Reading of 8+ v at Q2 c .. I did adjust the trimmer to 3v
    Earlier. I’ve only changed the fuzz pot ( only have 10kB )
    And now can only get 8+v .. what have I done ???
    It all still works I just want correct voltages..
    Q1 - 2N3904
    Q2- 2N5089
    Awesome site
    Thanks for your help

    1. I suspect using the wrong pot value is throwing your voltages off. If it works and sounds good why worry about the voltages?

  5. Is there original fuzzface layout..i mean t o say ac128 pnp