Bad Pixel MkII

[Mcentee2]

Just picked one of these up, looks awesome, and can get quite a lot of tones out of it.

A quick look inside shows these trannies and voltages (all negative really!!)

Q1 mp20
C 8.98
B 0.04v
E 0.0v


Q2 mp26a
C 1.01v
E 0v
B 0.08v

Q3 mp20
c 8.85v CW to .94v ccw:
e .87v
B 1.01v

Q3c has a bias knob that varies the voltage as indicated.

I haven't yet worked out (or can see) the rest of the circuit re resistors

It does oscillate when using a battery with attack full up and the bias giving q3c the full 8.85v, but it doesn't do it with a PSU or an alkaline battery, reducing attack or bias (lowering q3c) slightly gets rid of it,no problem really as I think that can be a common thing.

My eye was drawn by the Q2c/Q3b voltage at 1.01v, which is way higher than the circa 0.1v I have seen in threads.

What effect does this have on tone/clipping/saturation etc ?

I am guessing that Q2 probably isn't very leaky, and there is more swing available before clipping on that side of the signal going into Q3 - maybe a smoother thicker sound?

The Q3c bias control does what I would expect, with voltage on full up it is a much thicker less compressed, almost "blatty" cleaner, and louder sound, reducing the Q3c voltage brings in more "fuzz", sustain, loses some volume and low end.

Not an expert, just guessing wildly!!