Old tube plate > out transformer matchup list?

[systemtruck]

Anybody happen to know of a resource of common tube plate > output transformer impedance matchups for both single ended and PP applications?
I swear I’ve seen full lists in some Stancor or UTC catalogs but have been searching for that again with no luck for weeks now.
I’ve got a handful of tubes and transformers that I’d like to try some projects with but am not sure about compatibility.
At the moment I’m curious about making a single ended output with a 6SL7 going into a 7K:600 transformer.

 

[emrr]

Rule of thumb is take tube manual stated plate resistance for a given condition and x2 that value for what follows. But you see every possible variation in practice. 7K is a pretty heavy load for 6SL7 with it's plate resistance of 44K. Lots of gain lost and distortion components from that loading.

There's a Gates program amp output that achieves +24dBm output with paralleled 6SN7 into a 7Kish direct feed transformer, but it also has to carry 25mA of current, not easily found.

 

[systemtruck]

Rule of thumb is take tube manual stated plate resistance for a given condition and x2 that value for what follows. But you see every possible variation in practice. 7K is a pretty heavy load for 6SL7 with it's plate resistance of 44K. Lots of gain lost and distortion components from that loading.

There's a Gates program amp output that achieves +24dBm output with paralleled 6SN7 into a 7Kish direct feed transformer, but it also has to carry 25mA of current, not easily found.

Ok great, understood, thank you this is quite helpful !