Tube Matching Primer

Hi all. I'm in the process of rolling tubes for the new Cary 303/300 cd player and I am a novice in tubes. I understand from reading earlier posts that tube matching may not be critical in low power applications like cd players or preamps. However, I would still like to understand what matching is and what the numbers mean. Thanks in advance for your help.
Thanks Jay. I assume "very linear tubes" are those with a wide, even frequency response and the only way to test that is with your ears, which is what I'm doing (it's really kind of fun).

Any advice on tube matching? I read a lot about tube matching and I'm not sure how to match, what the numbers mean, what the acceptable tolerances are and so forth. Any insight and advice would be appreciated from the community.
Hi, Ozfly:
Wish I could help you, but I don't know how to read the numbers. Hopefully, someone reading this will educate us both.
Best wishes,
As far as reading the numbers and matching goes,
I believe thay have to be tested on the same tester to match do to the calibration of the tester.

I think that different brands of testers have their own rating tables as far as a bad, good and tests as new.

I'm sure that other members here with more experience than I will be posting soon to help you.

As stated in previous post, microphonics will show up if used in a preamp. A tube can test as new, but have very bad microphonics. Try and buy from someone that actually tests for that if buying tubes for your pre, I learned the hard way!
Thanks again Jay and Dcrookham53. I hope my question wasn't too naive or vague since there were no other responses -- unfortunately, I'm a tube novice. If anyone needs more clarification to my question, please let me know.