ZHBoost

From the post

Another submini tube based booster/overdrive pedal created by himister over at FSB, schematic. Make sure you are rated at least 25V due to the increased voltage from the rectifier. An additional mod you can do is replace the trimmer with a 250k pot so you can control the distortion produced by the tube on the fly externally.

A quick note about the power. In the schematic it states that the voltage is +9VAC, not +9VDC, but if you read through the thread himister states that he used +9VDC to test it and the pedal worked fine and correctly, which is why I put the voltage as +9VDC.

Modded with asymmetrical clipping diodes to provide some more distortion, and a gain pot that controls how much the diodes are in the circuit, similar to the Germanium Giant, as well as a basic tone control.

Modded with symmetrical clipping diodes to provide some more distortion, and a gain pot that controls how much the diodes are in the circuit, similar to the Germanium Giant, as well as a basic tone control.

Same layouts as above with the change to the power section. I decided to not include an onboard charge pump as it's just as easy to add one offboard with the available charge pump layouts on the site.

Non-modded layout:

Modded Layout with Asymmetrical Diodes:

Modded Layout with Symmetrical Diodes: