Nick Williams of Dunwich Amps take on the Buzzaround circuit. The most notable mods are the silicon transistors in the preamp section, a big muff tonestack with a recovery stage.
Schematic can be downloaded HERE.
Nick Williams of Dunwich Amps take on the Buzzaround circuit. The most notable mods are the silicon transistors in the preamp section, a big muff tonestack with a recovery stage.
Schematic can be downloaded HERE.
Built and working! Any idea how exactly to bias Q3? Seems like the balance knob is acting as a bias in tandem with the trim pot, so I'm not sure if it should be turned up, down, or in the middle when biasing. And I didn't see any instructions for it in the build doc.
ReplyDeleteGreat! I'll tag it.
ReplyDeleteYes, you are correct about the Balance control, it is basically a bias control.
The trimpot setting depends on the leakage of Q3. By adding resistance across the base and collector you sort of simulate leakage for Q3. Generally, 2N130x devices has quite low leakage compared to the Q3transistor in vintage Buzzarounds and TB3s. I guess you should let your ears decide but more resistance *should* sound better than less.
The trimpot can be left out if you are using a leaky NPN tranny like AC127, AC176, GT404 etc.
Super helpful! I was switching between GT404 and AC127s. Can I just pull the trimpot from the circuit then or is there any other modifications I'd need to make?
ReplyDeleteYeah, with the corretc leakage, you can omit the trimpot. I usually shoot for around 300mA.
Deleteawesome. thanks!!
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ReplyDeleteK1 is input location, correct?
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