NOS Tubes for Rogue Tempest II


Looking for some suggestions replacing the stock tubes. I want a little more transparency or pop yet retaining overall smoothness and good bass. I want to start with the 12AX7's and the 6SN7's first. I was told the Sylvania 6SN7 GTB would be a good one but there are several versions so I am a little confused. Also the same with the 12AX7 what is a good value without breaking the bank.
samzx12
I forgot to add the seller gave me a pair of NOS RCA 12ax7 cleartops for my integrated. I have not put them in yet but he said they were a warm sounding tube. It doesn't sound like they are as warm as the Mullards you speak of.

I used some GE 12au7's on a preamp I used to have. They weren't NOS but sounded pretty good and were not very expensive.

In my Rogue Cronus Magnum for the 12 ax 7s I have used the sylvanias 5751, but prefer the little warmer sound of Tungsols 5751s
From what a mainly gather most people seem to like the 5751's better than the 12ax7. The two times I have tried 5751's in place of 12ax7's they sound more musical and focused.
The 5751's work well in my unit too. I like to roll tubes as it's give a very different presentation. I'm currently using Sylvania 3 mica black plates with some Mullard's and it's a very midrange centered presentation. Sometimes I like the GE triple mica black plates together with Valvo tubes and when I want things to sparkle I through in my Siemens combo. All have a very different sound. Each has some advantages and disadvantages. But ultimately it's up to you and what you prefer.
Hey Sam - my Telefunkens 12AX7 arrived today, and I'm liking them a lot.

I've been doing a lot of rolling the past several days (both 12AU7 and 12AX7/5751), but came full circle back to the RCA Clear Top 12AU7As now paired with the Telefunkens - this is a very nice combo. Airy, spacious and more high end sparkle than the Mullards (when paired with the same 12AU7s). I think I still prefer the GE 5 star 5751s to the Telefunkens, and the Telefunkens over the Mullards, but I'm going to stick with this combo for a while.