The original schematic for the 385 was killing me - just too many part numbers listed, so I cleaned it up a bit. I also removed the projector circuits.
I think there are two versions of this amp - this is the 6V6 version, while the other uses EL84s (which is nearly impossible to find a schematic for).
BELL& HOWELL - FILMOSOUND MODEL 385 SCHEMATIC
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After the clean-up, I redrew the schematic in LTspice. Seems to work as expected, so hopefully no mistakes...
The tone control is unique, as it uses a dual pot for the James EQ instead of separate pots for bass and treble. Bass is cut while treble is turned up, and vice versa - or you could wire it so both bass and treble go up and down at the same time, leaving the midrange alone... interesting.
The dual 3meg pot is not easily found these days - in theory, resistor and capacitor values can be scaled to work with a 1meg pot, however, after spending some time on this, I can't get the response to match. It's roughly the same, but there are obvious differences.
Hard not to notice all the little caps rolling off some highs from plates of the 12AX7 gain stages. Something to experiment with and tune to taste.
Original pages below
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