Optional clipping switch
If you take the clipping diodes out of the
circuit you get a completely different crunchy
beast. It’s certainly worth trying the circuit
without them - test it before you add the
S1-S2 jumper. If you want to add a switch to
take them in and out, simply wire up a SPST
or SPDT toggle as shown. SPST will only have
two lugs of course.