I have a lot of tube knowledge in general about the various tubes I use. The EL34 and 12AX7 types I really don;t a whole lot about but I am rapidly learning.
I see in many of the 12AX7 variants that they refer to a long plate 17mm or short plate 15mm
What are people's experiences and opinions with them? Is one really better than the other? With 12AT7's the longer plate variants can sound superior but also are more prone to microphonics. Is the same true for 12AX7 long plates?