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

why not? if you have them

i would also use spell check and re-read what i am posting, if for no other reason than to be considerate of others

@jjss49, perhaps you should consider that English is not everyone’s first language.  

Tube Confidence:

This is one of the reasons I suggest tube people buy a simple tube tester. Not sophisticated testing, but enough to give confidence in any NEW or USED tube: no short; decent strength; for pairs, essentially same location in the ’good’ area (not likely to cause balance issues).

here is a simple one

https://www.ebay.com/itm/Vintage-Sencore-TC136-Tube-Tester-with-Manual-good-condition/143927443123?h...

here’s mine

https://www.ebay.com/itm/Accurate-Instruments-Tube-Tester-Model-151-with-157-model-manual/2548323165...

I have a big Hickock, and gave my friend a big Jackson. As far as shorts and strength, the little one always gives me the same answer. Very lightweight, portable, take to friends house ...

make sure you get the manual with tube listing booklet with it.

Also, verify it can test your tube types with seller. Mine does not have sockets to test a few types I have run across.

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.