FYI. . .Telefunken had TWO plants. One of them was in EAST Germany ("made in Germany") and had literally no access to fine metalurgy and so production was largely junk. LOTS of junk was produced. All say "Telefunken", all say "made in Germany", and all have a diamond logo on the bottom, and all have nearly the same packaging as the West German plant. True West German Telefunkens typically (this varies) have rather poor logo printing on the tubes. It is so confusing that I often prefer used "pulls" from McIntosh, Fisher, Eico, and Dynaco gear from the sixties. True West German Telefunkens typically last a lot longer than other tube brands (this depends on the circuit they are in), so if they test good, they usually are good. Neuteral in tone, detailed, and not at all rounded speaks for the sonic character. Be careful so as to not spend gobs of cash for the gobs of junky East German tubes that flood the market. Happy listening.
Which Telefunken 12ax7
I'd like to hear from members who are familiar with NOS Telefunken 12ax7s from the 1950&60s. I've spoken with three different tube vendors who are frequently recommended on this forum and received three different assessments of the ribbed vs smooth plate versions. One vendor said there was no sonic difference, while the other two were opposed as to which was warmer and which was more detailed. I sure would appreciate it if you guys could help straighten this out.