The way this is done is by using a very low input impedance and very high gain silicon transistors as well as built-in asymmetrical clipping. I chose the BC848 transistor, the 12th generation of the BC108 family, not because it’s better than its contemporaries, but because you and me both know you secretly want the great great great great great great great great great great grandchild of the most legendary silicon transistor ever in your new fuzz pedal, so why not?
Low input impedance means don’t stick it after a buffer or an unbuffered wah and please don’t expect the output or gain you’ll find in ODIN or BERSERK. You can do whatever you want, but if you were to use this like I do, with a low output, single coil guitar, into a roaring, distorted Marshall style amp and use your guitar’s volume knob to get your clean tone, I think you’ll find there’s nothing else quite as magnificent as HEDDA. It’s an extension of your guitar – an extension of you as an artist.
The secondary foot switch momentarily engages the feedback loop glitch switch.
As long as you hold it down, the circuit output is fed back to the circuit input for synthy, theremin-like oscillation, also controllable via your guitar’s onboard controls. The big knob controls your volume and the small control sets your bias, from 70s overbiased, sustainy leads through all the Jimi stuff and all the way into a sort of muted trumpet texture fully clockwise. Always experiment with your guitar’s volume control to find further sounds within it. I hid a weird tremolo in there too.