Tube Replacement Advice

I believe the 7316 is a 12au7 sub NOT a 12at7. The Sylvania Gold Brand 6201 is a great 12at7

William you are correct. I was looking at a zip lock bag of replacement tubes and the 12 AT and 12 AU were together, remnants of my days with Atma-Sphere.

The 7316 is a replacement for the 12 AU and works wonderfully in the older driver circuit of the MA 2.

For EL84, the best but near impossible to find is Lorenz. The second best(s) - Valvo disk getter then Telefunken.