This is a single channel version of Sunn Beta Bass & Lead Preamps.
You can find the original FSB thread here.
There are two different sets of caps depending on which version you want to build.
You could use Mark’s Bipolar Voltage Converter if you want:
http://tagboardeffects.blogspot.fr/2014/01/bipolar-voltage-converter.html
You could also use this external board to wire a Bass/Lead Switch instead of using fixed caps:
(20/H, 19/C, 22/J.. are board’s points coordinates where C1-4 should be placed)
If you want to build the original A/B Channels version just build 2 identical circuits and connect their outputs to the daughterboad below
