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I built this to Throbak spec but realized the C1k Gain pot was far more effective (as suggested in the build docs). I used 2N2222a transistors but also liked the sound of BC108 transistors, so I socketed Q1-3 to switch back and forth easily!
– Throbak spec with C1k gain pot
A transistor based boost which works at 18v. Artwork has been silkscreen in two colors.
Charge pump etched mini board added to give 18V when running on a regular 9v adapter. I used PN3565 transistors which work just fine.
Ok… to start off, I screwed up this build. Or shall I say happy accident? I intended to build an overdriver circuit, but when I made my bill of materials, I didn’t realize I was reading off the Power Boost page until after I finished building. I also forgot to order trimpots for my build. Oh man, that’s bad. I happened to have some 100k trimpots on hand and I just threw them in. They did the job, but they were pretty difficult to adjust for biasing since a little tiny twist is a pretty big change in resistance for a 100k as compared to a 10k. Anywho, it still worked. I used BC-109 transistors and I built it into a 125B enclosure with the included 1590 drilling template. Small bear messed up and sent me 1k linear pots instead of the reverse audio taper pots. While I wait for them to resend me parts, I’m using the linear pot that they sent me by mistake. It’s still pretty damn good.
So yeah, it was a happy accident coz I like the idea of having an 18V boost pedal. I haven’t yet used 18V with it; I am super happy with the sound of it using 9V. It’s like having a fuzz face but with a lot more control over the gain. I can make it sound bright or woofy. I can dial the gain down low and get a pretty sweet boost or crank the gain and get a growly fuzz. It interacts very well with fuzz pedals. It’s a really awesome effect!