I heard the wood laid in the canals in venice for at least a century before it was fileted to make the great instruments of yore. For tubes, I'll bet they simply cull fewer of the slugs from each run than they used to. So your chances of getting junk are higher. I'm with Grogan, sell 'em crap they have to replace sooner.
NOS tubes, why can't modern tubes sound better?
Perhaps this is a useless thread, but why can't currently manufactured tubes at least equal the sound quality of NOS? With the advances in science, why is it that a modern factory cannot exceed the sound quality of the past? Perhaps for the same unexplained reasons that modern violin manufacturers cannot attain the 'Strats'.