Wednesday, September 17, 2014

The Double Filter Revisited: Junction Machine

Alright so I've come back around to working on the double filter pedal and have made it much simpler on myself.  Basically I have implemented a variable capacitor at the beginning of an LPB-1 with a footswitchable potentiometer to let me switch between boosting frequencies.  I socketed the two input capacitors and the output capacitor of the LPB-1. This basically makes it so that I can switch out the range of the frequency at a later date.  At the moment I need to go back in modify the range of the pedal.  Its looking like I need larger output capacitors to let more bass go though, as well as larger capacitors on one end of my variable capacitor.

If you've seen Kit Rae's big muff page, he has a lot of schematics on there.  The idea of using an input "Depth" or "Focus" is where this originated.  A quick glimpse at the Supercolyder is where I'll be heading next with the Capacitor selection.  I think having a 10uF capacitor at the output should be good enough to let all frequencies pass through, and having a 10uF and 0.01uF at the input capacitor will allow for a drastic range across the frequency sweep.

Much thanks to Micah over at Glass Hero for his help.  His website is down, but he makes some awesome pedals!! Check out his facebook in the meantime.