power pentode Vs beam power tube

[Andy Le Blanc]

I'm looking at a PT, it'll do 200 ma. at around 330v, a nice low B+ and 100 ma. at 50%. And as the mental mastication proceeds, starting figure just what to do with it.
The low B+ allows me to explore power types that typically run from 250v to 300v plate voltage.
So I start looking in the RCA application and types column in the RC manual, trying to avoid types I've already noodled around with, 6v6, 6bq5....
At the bottom of the list, are older types and renewals and after comparing max plate dissipation find a 6f6 with a combined plate and screen dissipation not too far off a 6v6.
After some more digging I find its has the same figures as a 2a5, comes also as a 42,... kt63,vt66, I like the 2a5 bit.

Old school tube type, well established prior to the early 30's and superseded by 6v6 and beam types, at least its a pentode.

SO the questions are,... will it hold up in a guitar rig? how will it react in guitar rig? Has anyone any experience with the type?

One statement I've found is that it is sensitive to input and doesn't require much drive signal. And its still a $10 tube nos.

[Stevem]

In general a pentode output will have a smoother dynamic range then a beam type , but that's no guarantee that it will drive with less signal then a 6V6 and that can be effected by many other factors.

[Andy Le Blanc]

Okay,... I got digging in the heap and found one. A Sylvania, I can explore in a Champ. I think I have a 6w6 and metal type 6v6 to compare.
I did find a source for 6f6/vt66, metal and G/GT, pairs, quads, and matching. A bit surprised actually, positive motion.