Okay guys, maybe this is not the right place to post this topic, but I'd really like to understand how it works. It sounds like a fuzz factory on steroids, on to much steroids.. On an overwhelmed amount of steroids. I have no idea on how it might generate this sounds. The only thing I figured out is that the Filter rotary switch has the same effect of the switch on the fat fuzz factory, so it changes the value of the capacitor filter (I'm not sure of what I'm talking about, sorry). Here's a video
http://youtu.be/cal2RUoqvEQ . I tried to find some schematics , but I found nothing.