Used tubes question


I bought a used quad of xf2's. They were cheap, 150.00 bucks, so I figured I'd give this older-mullard-tube-thing one reads about so much a listen. Now I worry about putting them in my intergrated. I have a Leben CS-600 and fear it going up in flames. The seller said they were closely matched and tested on his such and such tester. He had plenty of positive feedback. Should I just pop 'em in and see what happens? What is the worst that can happen?
128x128oldsalt
Agree with Steidlguitars.

Buying old used tubes is a good way to go. I've been particularly lucky along these lines.

Normally, these older tubes have held up very well over time, a tribute to build quality which is not replicated today. If you can give up the snob factor of NOS, there are some real gems to be found at comfortable pricing.
Thanks everyone.
Any suggestions on what to look for in a tube tester? And, will testing tubes keep me from damaging my amp? What should I be on the look out, or, ear out for, when I turn the amp on that might signify a problem? Distortion? Weird tube colors? 10 foot flames?
Thanks again.
They sound fan-f*ing-tastic. Wow. I'm going to save up for a NOS pair or two. Wow, wow, wow....
Borders on a musical epiphany, does it not? As Trelja noted: The built quality back then was much better than that exhibited in today's manufacturing. Try to locate either TungSol or Sylvania 6CS7 dual triodes, for the preamp section(must be closely matched pairs and low noise). Small signal tubes have a major effect on presentation. Many don't realize how much can be gained with a NOS tube in the power supply. Replace that 6CJ3 rectifier for even more musical enjoyment. Welcome to the wonderful world of tube rolling. Happy listening!! =8^)
Yes. Yes. Yes.
I've removed the tubes from the amp and encased them in 20 layers of silk velvet. I'm thinking I will only put them in for special occasions. Why waste them on the kids when they are listening to Dan Zanes! No disrespect to the very talented Mr. Zanes intended.
I guess I should just find a NOS quad.
I just ordered some Sylvania 6CS7's today. What about RCA 6CS7's? Do you know of a source for Tung Sol 6CS7's? Really, the rectifier will make that much difference?