Just a note that NIB NOS Telefunken's tend to slightly red plate and will not last as long as the Siemens, I have rolled Mullard, Mazda, and Amperex. The Telefunkens seem to lift the music up and forward, more air. All are reasonably priced. I also noted that they should be close in current draw and mutual conductance or one of tubes will definitely red plate.
I have no schematic to determine how they are tied together or whats common to them.
|