FirstThe Clark Gainster is a rare and not too hyped drive pedal. Its one of the sweetest sounding drive pedals ive ever heard so far though.
The clark gainster has a very simple circuit, but sometimes less is more.
The gainster can be built with Mojo parts or not. This article is more about the mojo part one ;) I called my version of the Mojo Gainster: Mojo Drive ;)
Because mojo parts are not small, the enclosure should be big enough and the whole has to be built on a vero ;) you can use existing veros. i just built the vero up by myself.
For the non mojo version the Egghead PCB from madbean can be used.
The Clark Gainster can be built up with 3 or 4 pots. Drive, Tone, Gain and optional the Bottom Pot, which an be used to cut / add bass frequencies. In my built i didnt use the Bottom pot.
You may have heard of the Hoochee Mama Pedal. Its a 3 knob clark gainster clone with mojo parts and used by Coco montoya and lance lopez.
SchematicThis schematic shows the circuit for 3 pots and also the addition for the 4th pot. You simply need one more cap for the 4th one.
I found out, that the PIO caps (paper in oil) are kind of rare. I ordered them directly from russia.
All other parts are available at musikding.de. you can also order a nice vero board there.
Tip: I used single core hard wires, they also hold the board ;)
Other mojo parts are the Mallory caps and the Carbon Comp resistors.
the IC and the diodes are not so critical. you can use a TL072, LF353 or any 4558 chip for the IC, and 1n4148 or 1n914 for the diodes.
In my build I used a JRC4558 chip (as in the hoochee mama). Also the Hoochee Mama uses either a tropical fish or a orange drop capacitor as output capacitor (100nF before the Volume pot).
In my schematic i added a 100uF elco and a reversed 1n4001 (polarity protection) between 9V and ground.