freestompboxes.org

I continue to trace my Exar pedals - today, it's Exar KM-03 Kamikaze. That particular model seems to be quite popular in Poland back in time because I've seen some good mentions about it. I had two units; both had the same components inside, so I traced the one in a slightly worse condition. For another one, I have a box and user manual.
PCB is standard for Exar series 3. However, it uses two SMD ICs, which is rare in Exar pedals. There are many non-populated components; I guess the identical PCB was also used for other models.
The circuit has some similarities with Exar HM-02 Heavy Metal I traced before, as I thought initially. Sound-wise, it's a bit more exciting and flexible. First, we have the DS-2 discrete op-amp gain stage in Turbo mode (it has 2nd order Sllen-Key filter in front of the discrete op-amp). Then the signal splits into an unfiltered raw op-amp clipped signal (Mix pot) that goes into the mixer stage. Another part went through the hard-clipping diodes and split again into three paths: 3rd order Sallen-Key lowpass filter (Low pot), Multiple feedback highpass (High pot), and bandpass filters (Mid pot). Each Mix, Low, Mid, and High potentiometer controls the amount of signal mixed back. Such a tone stack is something quite rare for a guitar pedal. After EQ/Mixer stage, there is a standard BJT output buffer. Attached is the schematic with buffered bypass parts omitted.