Bocchi the horror: PPCB Cobalt Drive (BOSS BD-2 Blues Driver - Keeley mod)

[Hetari Gotoh]

Build Rating

5.00 star(s)

This is actually my first graphic "design" and the second pedal I decided to build at the beginning of my journey, but I knew I needed some experience before tackling it.

I used a 500K gain pot with 470K resistors between pin 1 and 3 and SMD J201 on adapter boards. It wasn't strictly necessary but I selected 4 with similar values and balanced them using this guide by Chuck D. Bones, resulting in a 7k value for R5 and 7.4k value for R7. R7 needed some more tweaking but I wasn't particularly keen on having "The Resistor Centipede (Second Stage)" on my board.

I can't even remember why I wanted to include the Keeley mod. I did so by following an article by the tone geek, leaving out the silver mica because I wasn't modding an original boss pedal and 3/4 of this mod probably has no real impact on the end result anyway (modding the mostly cosmetic clipping diodes for instance).
The ON/OFF/ON SPDT has 15nF and 50nF capacitors connected in parallel to the original 18nF on C14, providing 33/18/68 values (chubby / normal / fat).

Later I found this post that my future self will follow the next time that a Keeley mod will be needed.

The whole contraption is a bit noisier than I'd like but very nice. More pointless and cruel experiments will be conducted on the poor BD-2 in the future.

 

[swelchy]

WTH... Second build. That's insanely impressive. A++

 

[Hetari Gotoh]

More like twenty-fifth build. Had I attempted this as my second, this post would have been in the troubleshooting section. Perhaps I've gotten slightly better at assembling pedals, but my communication skills and my english are getting worse. Thank you so much anyway.