NOS Tubes for Rogue Tempest II

Yeah when I bought the amps the dealer requested NOS tubes with them, I believe.

I have RCA clear top 12AU7s in my amps now and love them (they were a Rogue recommendation) but I haven't heard a 12AX7 (M180s use 2x12AU7 and 1x12AX7 each). Great, another thing to buy!! ;)

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.