With the change to smaller output capacitors and the use of disposable camera flash capacitors. It looks as if you have developed a bang for the buck preamplifier.

What type of power supply filter scheme are you using, CLCLRC, or?

How did the overall sound character change, when you changed to the 10k plate load at 10mA and 4 red LED's at the cathode?
This must have reduced the overall gain somewhat?

Now, if I can figure out how to get a cheap power transformer to obtain the 170V without a big series resistor to drop some Voltage.

This preamplifier could be built from mostly junk box parts.

It would be nice to have a great preamplifier with a tiny investment.

As always, thanks for your input.

Norris