Power: Good or Bad

For vocals and acoustic instruments, go with a SET amp and high sensitivity/high impedance loudspeakers. I can't imagine there will be much disagreement with this suggestion.

On the other hand, a good friend recently purchased some George Wright Signature push-pull monoblocks. My friend has owned SET amps, and owns Klipschorns. He says the Wrights are the best amps (clear, musical, pure) that he has ever owned.

FWIW.

You know, just about the time that I thought I had categorized the sound of various amp designs, I would hear another that broke all the rules. There are so many variables that I don't think you can do better than offer rules-of-thumbs about how a certain design will affect the sound. As far as power, it has been my personal experience that more power results in better bass, dynamics, and of course, ultimate loudness. That is about it. I have heard low-powered solid-state amps that were quick and detailed, while other higher-powered amps had the edge in those areas. Same in soundstaging and dimensionality. Of course it depends on your speakers and other electronics, as well as what you deem important. I tried SET amps with my Wilson speakers and just didn't find that sense of dynamics with the types of music that I played. But perhaps on more efficient speakers I would have preferred the low-powered SET's. I always liked Class A amps better than AB amps but recently bought both a class A and an AB amp from the same manufacturer and preferred the AB (maybe because the AB amp has an unusually wide bandwidth of 5+ MHz). So my take is that you have to listen and decide for yourself. Probably not the answer you wanted.

I think a great designer can design a great sounding high power amp. I own CAT JL2s which are 100 Watt, Class Triodes. They are powerful and delicate and among the best sounding amps in the world IMHO. But, the amp to my non-engineering eye is complex, lots of parts and lots of transformer - the amp weighs 180lbs! I think Ken Stevens is a brilliant designer, capable of designing a world class, high powered amp competive with SETs at their own game. But, I suspect he could do something even better if he knew that a speaker could be handle with just 30 Watts. Of course, he would have a much less universally useable amp - the JL2 can drive almost any speaker, and can be sold to many more potential customers.

If you want to hit 115 dB peaks, I hope that you're planning to do some sound treatment work to your listening room! Sometimes, it's the listening room that "poops out" first, and not your audio gear.

+++ I tried SET amps with my Wilson speakers and just didn't find that sense of dynamics ... +++

Wilson's are known to be demanding to drive, and as such not SET friendly. Hardly an meaningful statement.

+++ I think a great designer can design a great sounding high power amp +++

There is no black magic in electronics. Each time the signal goes through a component it deteriorates. No ifs, no buts, no maybes. The larger the amp, the more amplification stages, the longer the signal path, more feedback stages, more coupling caps/trans, more resistors etc. etc.

If you ever bothered to upgrade components, you know the difference even a single high quality coupling cam or signal path resistor makes. The best coupling cap is no coupling cap. The best signal path resistor is no signal path resistor.

All things equal, the small amp smokes a bigger amp ... always.

Regards
Paul