Op-amp

[stevenrotterdam]

Maybe a stupid question
But how about driving difficult tubes like 845 with a high voltage op-amp?
Yes I see that the opamp costs the same as a nice interstage transformer.

https://docs.rs-online.com/080a/0900766b80ef3d69.pdf

 

[dreamth]

20v/us slew rate in a 500v output stage...a bit too slow in my opinion.

 

[jan.didden]

Your question is a bit vague. Are you looking for a circuit?
There are MUCH cheaper opamps with up to +/-100V and over supplies.
Check ADI and TI.

Jan