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Here is my redraw of the schematic. I have not opened up the amp to confirm this, but a two-stage NPN preamp should look like this... Also, the unmarked capacitor is likely a 0u01 based on the similar Marshall schematic which this one is probably copied from.

I suspect the pin out of the transistor is different from how you drew it here. From the spec, the pins are 1=E, 2=C, 3=B. As drawn, it looks like you interpreted them as 1=C, 2=B, 3=E. I redrew the schematic with the revised pin out and it makes more sense now as a two stage amplifier into a twin-T tone control and volume.

Yes, this is two years old, but I've done a lot of mods on these amps and stumbled into the thread.