You really really want to reduce the gain?
Wanna make it into a buffer amp?
Are you brave enough to re-configure your amp?
From SRPP to a boot strapped Cathode Follower with tube active load...
I'll just maintain the operating points of the tubes, that will save me some calculations chore.
I won't even have to know the Q point of the tube
and should anything go wrong, nothing should burn
Top triode mod,
- Connect a 1M 1/4W resistor from top triode grid to the anode of the bottom triode ( or in another word, replace the wire between the top triode grid to bottom triode anode with a 1M 1/4w resistor)
Connect a 0.01uF/600V film cap as input cap to the grid.
Connect a 1M 1/4W grid resistor on the other end (input end) of the film cap to ground.
Connect the volume pot to the input end of the cap.
#many ppl omit this input grid resistor to save 10 cent and use the volume pot to do two jobs, to me this kills the sensitivity. but beware, with the improved sensitivity comes all sort of noise which were blurred prviously... such as filament hum, poor layout noise... etc etc... more improvement shoud come. If no such noise, then call yourself lucky.
Connect a 1M 1/4 grid resistor from the grid to the ground end of the cathode resistor of the bottom triode.
Others should remain unchange.
Too lazy to draw the circuit.
you should get gain of mu/(1+mu)=0.93
Zin? Very high higher then you can dream of,
Zo? should be at least lower then 800ohm.
All velues are not critical, except for the capacitor voltage rating, just make sure it is higher then your B+ will do. So don't beat yourself if you only have 1.2M or 860k resistors, or 0.1uf.
Won't know how it will sound but surely nothing should burn
Have a go.
## Ops its a mu-follower not SRPP