I dug into my Vox distortion booster again determined to make something good out of it.
In theory it should be a good sounding pedal because the circuit is actually a brilliant bastardization of classic pedals.
Basically it’s a tube screamer clipping stage fed into a distortion plus. The drive pot is a dual pot and controls the gain of both stages at the same time. Then it’s fed into another dual op amp driving and recovering a big muff style tone stack.
The problem with this pedal is all the capacitors are way too small and filter out every trace of bass and low mids. The values chosen for the tone stack are ridiculously small making it barely usable.
This thing in stock form is a fizzy trebly mess.
I’ve been trying to learn about actual circuit design so I didn’t want to just add a bunch of toggle switches or extra pots.
What I’ve done is enlarge most of the caps to let more bass in/through the circuit which also increases saturation.
The tube screamer circuit got a common bass boost mod so it doesn’t sound so utterly congested.
I changed the values in the distortion plus part of the circuit to stock d+ values with a bit more low pass filtering.
Then I fixed the tone stack with correct values for a big muff tone stack.
Now it can get nasal mid range ts style crunch on one end of the tone knob with the gain dialed back and big wooly saturation on the other end with the gain cranked.