Best suitable 845 Tubes for NAF 845 SE

I'm currently using Psvane 845T tubes from Grant Fidelity and like them better than any others I've tried. BUT I've bought a lot of 845s from Sophia and never blew any (over an 8-year period) while one of the 845Ts died after 14 months. So I would say you might have an amplifier issue rather than a tube issue. Have you used any other 845 tubes except the ones from Sophia, and how did they fare?

Which model Sophia 845 tubes did you purchase? Some of the 845 tubes that Sophia sells do not conform to the RCA/Amperex 845 operating standard, therefore, you could be using an 845 tube not spec'd for your amp.

The most reliable current production 845 tube is the Shuguang 845B. It sounds good, it handles the highest B+ voltage circuits and lasts. I have a seven years old pair in my Audion Black Shadow monoblocks and they still test well. You may find some sonic advantages to some of the more exotic alternatives, but I haven't found any of them to be as dead-reliable as the 845B. Another good alternative for a somewhat more aggressive sound is the cryogenic-treated 845A sold by ATSI.

Either of them drops into a standard RCA-spec 845 SET circuit.

Phil

I've lost one 845B after about 6 months and another one after 2 years. They were bought from an European dealer, premium quality not the ebay, from China stuff.