Current version Gold Lion 12AX7s are great tubes, and after trying various new and NOS options in my amp I'm now sticking with 'em. Note that the driver tubes in my amp are 12AT7s and I found that NOS Mullards not only sound great but "flash" when they start up, which illustrates my low threshold of entertainment. I used 4024s but switched to 6201s since they have gold pins…I like the gold pin thing in my gold plated (I think) tube sockets as that's one place I prefer to have proper metal contact…note to self: Get the tiny brush tube socket cleaner thing. Does anybody make gold pin power tubes yet?
12au7 or 12ax7
I recently purchased my first tube amp a Primaluna Prolouge 5, the previous owner said the tubes were at the end of their life. I replaced the factory KT-88's with Tung-Sol KT-120' with which I am very pleased. My questions is which would give me the biggest sonic benefit replacing the 12au7 or the 12ax7? Both will be replaced in time which do you think I should do first?