If you had a dozen pairs of classic vintage ubes in your closet

Whenever I buy NOS tubes I listen to them to make sure they work and aren't microphonic (which many I've purchased have been).  I like to switch tubes around, so they don't sit in a closet unused.

OP,

Remember, new ones need break-in. Brent Jesse told me: Leave on for around 60 hours (no signal required), then compare.

Are you saying listen to spares of the same brand? I would not bother unless I suspected a problem.

If you mean, try different brands, it is fun to satisfy curiosity and learn. I blew one, bought matched pair new 6SN7's for my Cayin, hated them.

Tried some old tubes I had in a drawer (I've got a lot of NOS and used), loved em. Brent Jesse let me return and exchange for new matched pairs of those, and they cost less, gave me a refund for the difference, no restocking charge.

It's not just the power tubes that can make very audible differences.

You can confirm your current choice sounds best, or find something else you might prefer.

Cost: nothing but time (after you buy a toy tester).

I have dozens of ubes Amperex and Mallard etc.

Great question. But before giving you an answer, I'll need somebody to send me a dozen pairs of classic vintage tubes. I'll get back to you after that.

@testpilot

i do consider people may not be native english speakers, when appropriate... but not in this case though... thus my comment

@midareff1

have a little pride man... just look at your post title and initial post ... when i type something, i re-read it, make sure people understand and there are no glaring omissions or misspellings... caps aside...

or maybe lay off the booze when you are posting and asking for others' input here?