wiring diagram of 2-stage circuit

 

So here you can see the two identical fuzz stages and the switch wiring which interconnects them.

The large 10u electrolytic is only on the input of the first stage; I'm not sure this large value is needed or wanted, I'm just blindly following the general design of the transistor version.  It seems like there are some slow, long-time-constant behaviours to the classic fuzz tone, and my supposition is that maybe this is due to some of the large capacitor values: both on the input, and in the gain control circuit.

The other coupling capacitors are standard tube amp values, 22n (or could also be 20n).  In 1-tube mode, the first stage is loaded by the 1M output pot.  In 2-tube mode, the first stage is loaded by the feedback network of the second stage, 33k into something like 500k equivalent to ground; and the second stage is then loaded by the 1M output pot.  Thus, there are no explicit load resistors.


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