Tube amp signal inversion

[guitar-rocker]

Hello all, I have a design for a amp where I want to blend two preamp signals that have opposing signal inversion (this is before the PI). Is there a better way to invert one of the signals rather than add a another triode to correct the signal ? I've searched several books, but only found the voltage divider input before the second stage to re-invert the signal.

[R.G.]

Conceptually, you can feed them to opposite grids of a diffamp-styled PI.

It's much harder to do with other PI circuits.

[xtian]

You could use a FET if not opposed to silicon.

[guitar-rocker]

You could use a FET if not opposed to silicon.

Would you be referring to using the FET in a cathode follower role, or just as an additional stage?

[John_P_WI]

Gain stage set to unity. Cathode followers don't invert. Look at using something like a LND150.

[guitar-rocker]

Duh, forgot that about CF's. Thank you.

[Stevem]

You will loose 10% of the forward voltage gain with the cathode follower though!

[roberto]

If you share the schematic we can help more.
Maybe you can just share one stage.

[rp]

Pretty sure the Vox AC30CC2 blends the two out of phase channels using a chip to flip the phase but the details are beyond my pay grade. Here's the service manual I'd verify it for you but modern schematics make my head hurt.

[The Ballzz]

Here's the service manual I'd verify it for you but modern schematics make my head hurt.

Amen, my friend! I agree whole heartedly!
Gene