[fado]

In this series some of the earlier versions have a single getter vs later versions with double getters; also, some have welded plates vs later one's without welded plates. 

1. Given similar condition, would one expect a difference in sound quality (pre-amplifier use) between single or double getters or welded vs non-welded plates?

2. Which would be preferred - rS or tv coded tubes?

3. Any other manufacturing characteristics one should look for when purchasing these very expensive tubes?

Thank You

[paul79]

To be honest, I cannot tell much of a difference in any of the different types of Mullard's or the Holland made GZ34's. They are all fantastic tubes and tough as nails.

[Ericus Rex]

AC member Adrianc seems to be our resident expert on old tubes.  I'd PM him your questions if I were you.