The 12AX7's that come with the PrimaLuna are very good; however, I would replace the 12AU7's with NOS RCA black top or clear top. I recommend Brent Jesse if you don't already have a "tube monger". In my opinion, NOS tube should be bought from "tube mongers" only.
The tubes I recommended are best for jazz and female vocalists. The tubes you select will be whatever is best for the music you like.
The tubes I recommended are best for jazz and female vocalists. The tubes you select will be whatever is best for the music you like.