Home made guitar amp overdrive

[RockNRoll!]

I killed an old toy I had laying around to use it's amplifier chip to make a guitar amp using the diagram in figure 16. I wanted overdrive so I took the output from one channel and connected it to the input on the other channel so now it has tons of distortion but it's a little too much so I want to hook up an overdrive knob. Would I just make a simple voltage divider like the one below with a potentiometer or is it more complicated? Any idea how many ohms the pot should be? Also would it be possible to make the input a little more sensitive? It doesn't pick up the guitar if it's it's playing a quiet note like tapping.

[Shugs81]

got to http://freestompboxes.org

I built a £130 pedal for about £40 using layouts from there... many many more i want to build!!

you'll probs be able to just build some monster pedals from there!

[Mario]

You always want to put the volume control on the input, never the output. You do use a voltage divider like you have there, but have the top pin come from the guitar, the middle pin go to the amp input, and the bottom pin to ground.