Personally, I am absolutely convinced that you can expand soundstage and depth quite dramatically by applying slew limiting and restrictions on the high and low frequency dynamics of the sound. It's similar to what happens when you hit tape, and for the same reasons- transformer stages, limitations on available energy.
Do that and you get a wonderful soundstage, which is not on the actual recording.
Not for me, thanks, I'd be more interested in minimizing the known problems with transistor circuits (like crossover distortion in Class AB circuits, ringing etc)
I can apply those characteristics digitally, thank you- did it to a very famous Telarc recording (their Firebird, old Soundstream recording) to show them what it would be like (waiting to see what they think of it- Telarc have been busy beavers lately, lot of work to do over there)
I would suggest whatever floats your boat for 'incredibly clean and pure transistor or FET power amp'. Brad, is that Pass Labs amp one of their SET-FET monsters? I'm thinking of making or getting something in the way of a Pass single-ended FET amp, since my big horns are reasonably efficient. What I have is the guts of an old Harman/Kardon, which is acceptable but really nothing that special, even all modded up.