Why aren't new vacuum tubes as good as old ones?


Why aren't new vacuum tubes as good as or better than old ones? Don't we have purer metals? Precision equipment? Why isn't anyone making the highly regarded 7316s?
pmboyd
When you guys talk about "better" that include sound quality?.
Yes and durability. One of the reason I read is some raw materials are banned due to environmental reasons so they can't produce the same quality tube.

Atmasphere, what's the name of the tube manufacturer in NV?
Hi Atmasphere, I am very interested with your finding of this new tube company in carson city, NV,, I believe if they have less dies, the tube will be made to last longer, and maybe be as good as ww 2 nos tubes, you said they were going to make the 12A-series tubes, I would be grateful if you could E-mail me information on them with pricing, if they have prices yet?, you can E-mail me thru audiogon here, thankyou Ralph.