On Feb 22, 9:36 am, "Theo" wrote:
Regarding the "all metal" tubes series by RCA,
can anyone tell me if there was ever a metal version
of the 6SN7?
I cannot find any reference on the web.
Any help would be greatly appreciated.

There were metal dual-triodes, like the 6SU7, that had the same basing
as a 6SN7. And there are lots of popular metal dual-triodes with
different basing (I'm thinking esp of the 6SC7).

I'm sure that some of the wash houses cleaned off 6SU7's, found the
market wanted more 6SN7's, and painted them as 6SN7's.

I'm 100% certain that some of the old-time retailers mentioned
elsewhere in this thread were selling washed/relabeled tubes. Heck, it
happens today still!

Tim.