It’s a challenge and even though I’ve been using tube gear almost exclusively since the early ’70s, I don’t pretend knowledge about tubes in the kind of depth that would allow me to avoid fakes or bad examples. In fact, some are not fake but are not what they purport to be-- a tube I bought with made in Gr. Britain on the glass was actually an Amperex tube made for Mullard or Siemens in the U.S. back in the day when the companies would seek out manufacturing capacity to cover demand. Or so I learned.
I feel you on the source limitations too. Most are pulls not really new old stock. And some sources I used have pretty much dried up. I too have an order with Andy. Some of the common audio tubes are now harder to find b/c they are so popular; some less common, like the 6H30, which is in my line stage, are getting rare as early DR stocks depleted.(I didn’t like the sound of the modern tube in my unit, the DR had far more ambience). I don’t think there is an easy answer unless it is gear that is designed to sound good using a modern, readily available tube.
I only roll 1 tube on my amps, Lamm ML2- the 12ax7- easy to find pulls, not so easy to find truly new old stock (ribbed) and that is an "easy" tube--- there were a lot made.
Even rectifiers, which used to be common and cheap are now pricey for the desirable ones.
I also like to have a back up or two for each tube so I’m not in extremis; and these days, some tubes are spendy. At least if you get true NOS on small tubes, they should have long life. The problem with pulls is they may measure well, but can decline far sooner b/c they really aren’t "new"-- how many miles on them? Who knows....
I feel you on the source limitations too. Most are pulls not really new old stock. And some sources I used have pretty much dried up. I too have an order with Andy. Some of the common audio tubes are now harder to find b/c they are so popular; some less common, like the 6H30, which is in my line stage, are getting rare as early DR stocks depleted.(I didn’t like the sound of the modern tube in my unit, the DR had far more ambience). I don’t think there is an easy answer unless it is gear that is designed to sound good using a modern, readily available tube.
I only roll 1 tube on my amps, Lamm ML2- the 12ax7- easy to find pulls, not so easy to find truly new old stock (ribbed) and that is an "easy" tube--- there were a lot made.
Even rectifiers, which used to be common and cheap are now pricey for the desirable ones.
I also like to have a back up or two for each tube so I’m not in extremis; and these days, some tubes are spendy. At least if you get true NOS on small tubes, they should have long life. The problem with pulls is they may measure well, but can decline far sooner b/c they really aren’t "new"-- how many miles on them? Who knows....