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, September 24, 2019

Brunetti Taxi Drive

Here's a pretty interesting lower gain overdrive. There's a an opamp gain stage with soft clipping going into a JFET stage that pushes a modified BMP tone stack, followed by a BJT output buffer. One of the diodes in the opamp stage is unknown, so socket and experiment. I also took a few liberties from the original using a TL072 instead of a TL071 for layout purposes and using the second opamp to buffer the voltage reference. Should fit nicely in a 1590B. Schematic available on FSB.


  1. Thanks for the layout. Maybe the diode in doubt could be a BAT41 or 1N60, because I believe it is just to have an asymmetric clip. You could provide your email address. I would like to submit a wah project.

    1. Whatever that diode is, it has a higher forward voltage than the 1N4148s. (1.5v vs .7 and .8v in the circuit) And send via faceboook if you don't mind.

  2. Thank you for all the great works here. I have built one on this layout but have too shrill tone. Compared to the schematic on FSB, I think R9(22k) between FET-Gate and 10nFCAP is missing. I'll try squeezing 22k into my build.

  3. As mentioned above, 22k is missing. Second 47n cap at the bottom is connected to ground but it should be b/w 1.5k and 220k resistor, and be connected to 220k and ground (or 4.5v) based on FSB. With the corrections, I verified. Very cool overdrive. Thank you for sharing.

  4. Me parece que falta um resistor na base do buffer de saída BJT, ligado a referência de tensão 4,5v...