5F6a preamp to Sunn PI?

[firemedic]

Would there be some sort of massive impedance mismatch or other problem with a 5F6a channel feeding a Sunn-style pentode/cathodyne?
An anode follower normally feeds the pentode; would a cathode follower work all right?

[PRR]

5F6a delivers about 2V to the lo-gain power stage.

Sunn power stage needs less than 1V, maybe under 0.5V.

It can work, Gain will be high, layout may be critical.

Why not a dual-triode driver instead of the scarce 7199 pentode-triode?

[firemedic]

It's really a 5879 feeding a 12AU7 triode cathodyne.
There's also a 1M master volume pot between the stack & the pentode, so I'll be able to get the PI input about right with the MV knob I think.

I have been juggling values all over this bass amp to get voltages & gain where I want them, & without an o-scope or real knowledge it's a fairly tedious trial & error slog.
One channel is an Ampeg B25b which sounds about dialed in, with stock values, and I'm finishing up the 2nd channel. It started life as a Weber 6S100 modified for bass but it's not working out as such.
 
See the "bass amp suggestions" thread to see the 4-month+ deal I'm dealin' in.