I just picked up four of the russian 6N7S tubes with the aspiration of puttng together some type of class A (AB-leaning-heavily-A at least) push-pull amp. I chose 6N7S's because they are readily available and they put out a decent amount of power. I was a bit surprised to see that they've been traditionally used for pure class B, but I hope they have some real hi-fi potential.
If each bottle has a 12W max dissipation, I'd dissipate around 20W per pair, hoping for around 10W of nice audio. Is this feasible? I don't have a printer so I haven't done any load line drawing, but let me make sure: with the PPP setup, the load impedance that EACH triode sees is the same as the anode to anode impedance of the OPT right? Any ideas about what OPT primary impedances might be best for such a project?
I'd have to look at some load-lines to see how much swing is needed to drive the tubes but I have a few 5687's kicking around that hopefully could be up to the task. Maybe an LTP feeding a regular grounded-cathode stage? a LTP'ed SRPP?
If such an amp isn't practical I'll just save these to use as somewhat beefy drivers for another future amp. Planning ahead, I am :)