Quote Originally Posted by dean_martin
When you try the GTs, I'd appreciate your opinions on them and I'd like to know where you found them. In the meantime, enjoy your holidays. I'm trying to round up all my Christmas music.
Kevin Deal at Upscale Audio likely has one of the most comprehensive inventories of tubes I've ever seen. He literally travels the world buying up old inventory of old stock vacuum tubes.

Once the tubes arrive in his warehouse, he burns them in, tests for reliability, and then assembles matched pairs. He's got some custom made racks which can prepare 30-40 tubes at a time. Then he's got the instrumentation on his workbench to measure performance and tolerances of each tube. It's quite an elaborate operation.

I bring up this subject because, you can call him. His knowledge of the different tube characteristics can help you tune your gear to your tastes. Do you want brighter top end? Quieter background, or larger sound stage? He can tell you which tubes will accomplish what you want in your equipment. When I was there for a recent club meeting, I saw a large box full of 12AU7s and their clone variants.

http://www.upscaleaudio.com/home.asp