Mammoth Electronics Nuclear Winter Distortion

[anders]

As requested, not verified at the moment.
Schematic at FSB

[JabboWookie]

[JabboWookie]

The schematic posted on FSB shows the tone section before the clipping diodes, whereas the schematic Mammoth sent me shows it after. Does that affect the vero layout at all?

[JabboWookie]

This is verified, I did make a few changes. Per Frank_NH in this thread: http://guitar-fx-layouts.42897.x6.nabble.com/Mammoth-Electronics-Nuclear-Winter-Distortion-td42541.html

-Replaced the 470k resistor from the gate of the J201 with a 1M resistor to ground
-Replaced the 6.8k resistor from the drain with a 22k resistor to bias the J201. Voltage gain ended up being around 7.5V, so a trimmer might work better here.
-Gain pot is backwards, should be 1&2 to ground, lug 3 to the 1K resistor (I used 2.2k here, which is what my schematic from Mammoth showed).

Sounds ok, gain is bunchy right at the end. Frank's suggestions solved the volume issues I was having with the original PCB that I bought from Mammoth (that I scrapped).

[Tesla]

Your going to want to get the drain voltage down to around 5v if you want it to sound “proper”. Right now the fet isn’t biased as designed ( just assuming as I’ve never seen a drain voltage that high on any fet stage beside a buffer of course which connects directly to power at the drain

[Tesla]

Fets are very inconsistent, unless they’re being sorted you can’t really just apply a fixed resistor to the drain and expect it to bias up as expected (unless your lucky of course ).  I’d play with that resistor until your voltage drops down to between 4.5-5v off a 9v supply.