This is interesting variation on the Tube Screamer style diode clipping. Read more about it at Mark Hammers site here: https://hammer.ampage.org/files/The_Crank.gif
In a nutshell the goal seems to be less distortion. More of a booster to overdrive effect. I’d say this circuit meets that goal. The sound is mostly clean with some gravel or grit as you get louder. It never gets fully distorted.
I designed the PCB in Eagle. Then had some boards manufacture at PCBWay.com. The cost was $50 for 10 boards, which is seriously cheap. The shipping costs were $20. By ganging this order with a couple other orders I kept the costs down to $1 per board. So $10 for 10 boards is better than making the boards by hand.
Sadly I mixed up the pots so the rotation is backwards. While I could fix this by cutting the legs on the posts and soldering some jumpers, I think I I’ll just make a new version of the board in the future. There were a couple other improvements I also want to make.
I designed the board with the pots and LED mounted to the board and off board wiring at the bottom edge. This makes for a very easy build.
I designed the graphics in Sketch and milled the enclosure on my desktop mill.
Last I wired everything up. With the offboard connections organized along the bottom of the board the build process is easy and prevents errors.
I may publish this one to the shared service but it will need an update first to fix the pots which operate backwards.
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