I agree with S23chang. RCA 5814's and 6189 COMMAND versions should also be considered if you can find them.
What are the best drop in subs for a 12AU7??
I am considering a Minimax preamp, but understand that they sound best with rolled 12AU7s. I have some Mullards which I would try first but have heard that there are even better choices of slightly different tubes. What are they and are they difficult to find? Thanks any help is appreciated.