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, July 28, 2015

Bearhug FET Compressor

Here's a simple compressor design by Jon Patton (aka midwayfair) that's good for guitar and bass. In Jon's words:

The Bearhug is a tonally transparent, ultra-quiet, tiny, and easy-to-build compressor. It occupies some middle ground between the ultra-subtle compressors like the Flatline/Afterlife and Orange Squeezer and the super squishy compressors like the Ross.

For more info on the design, Jon goes into detail in this thread on DIYSB.

I built this one last night and it's everything Jon says it is. Very subtle, and a little bit of volume boost if you want it. Here's a few pics of my build.


  1. Hey!! Just letting you know that the topmost 1n4148 is around the wrong way. Was having eons of strife with this circuit, but now it works :)

  2. It's a little bit different in schematics that there are in jon's site, more like the update of the first version, not the second version. Position of 2n5457 seems different, and also position of electrolitic condenser near volume 3 is different from schematics(negative at pin 3 in jon's schematics

  3. In the original scheme there is a trimpot, for the adjustment of the bias; Is it that even without the trimpot it works?

    1. Pretty sure Jon revised the schematic and this follows the newest version.