Took a look inside mine. And, I'll admit, my knowledge of electronic theory is limited, but it seems to be similar to the Big Muffs (Little and Russian). it has a 4-transisor circuit (on an attractive
RED board). And, internal layouts, input capacitors and Deep Switches aside, it's controls are essentially the same as the Muffs. Just has more low end response (in other words, I get the distortion out of my 15" driver instead of my little HF driver). It's a pretty sweet pedal. Pics of gizzards to follow.
The back of the board.
The 4 transitors.
Another view of the inside.
