i recently opened up my low pass cause i had to make an operation on it cause there was something stuck somewhere in the fooger and anyhow i came across a blue knob tat you can turn with a screwdriver… now my friend told me that that knob has something to do with calibration of the fooger so anyway i’m very interested if someone knows what that knob does 
Oh yeah…that thing makes it sound cool but you can really mess things up if you “take too much”.
i played with the knob settings and basicaly it controls the level of effect vs dry signal, at least thats the difference i heard when using the low pass
Man we analog junkies just can’t resist turning knobs huh lol.