Another drive circuit from Bajaman. He's been on a tear lately! In his words...
Here is my latest build based on the frequency response characteristics of the Diezel VH4 tube head channels 3 and 4, but scaled down into a 9v dc pedal friendly format... I got a chance to try using it on Neil Young's "Keep on Rockin' in the Free World" and needless to say it sounded awesome on very low gain setting Channel 3 - just the right amount of searing crunch and in my view one of my best pedals to date!
It will fit in either a 125B with top mounted jacks, or a 1590B with side jacks. If you go 1590B, you'll either have to offboard the pots or use long leg pcb-mount pots and populate them on the component side. I've added extra pads for the JFETs so you can use either DGS or GSD pinout transistors. Schematic can be found here.
This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.