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.

Monday, March 27, 2017

Hjärt Müller Bass Drive

Here's an overdrive for my fellow bass thumpers. Fairly simple opamp-based drive section with soft clipping pushing a Big Muff tone stack. Should be an easy fit for a 1590B with board mounted pots. Here's the schematic for reference.


  1. For "better" low end you could use 2x 1n MKT in series instead of 470p. You will get 500pF, byt with 20% tollerance, as 470p have, so, it will be no difference, but I have read that ceramic capacitors can't handle frequencies under 100 Hz. I was doing this "mod" in Ezekiel and friend bassist said that there are no low-end cut. Keleey mod for Rat also replaces ceramic capacitors by mika or MKT, as I read.

    1. IMO, values are values and material type only comes in affect in complex hi-fi systems. On dirt boxes, I now use cheapo ceramics for almost every cap below 1uf. You really can't hear any difference what-so-ever.
      Things like changing values as your first suggestion are what makes really noticeable changes. Also things like impedance, using buffers or pedals with buffers before fx chains matters much more to make the signal redundant throughout all the way. It doesn't matter if you use the best parts for a small gain in quality if it's going to turn to mud at the output.

      I just wanted to tell about what I experienced and read from knowledgeable people. It's important not to blindly follow fake cults like tone-wood stuff for me. haha Peace.

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  2. Hi, I would like to know if you have any effects made with bulbs. Thank you.