I think I have to agree with Arj here about Tube watts. I was astonished how the shindo 12 watts per channel amp drove a difficult to drive Usher mini dancer. This is a floor stander version of the 718be. The amp had the speaker's woofer's by its (you know what ) and what control it exhibited !
Every musical instrument in place, clean un-distorted power and supremely musical !
I do not think a 12 watts SS amp can do this with the Mini dancer.
Well, 12 Watts are 12 Watts, as arj and others have also said. But that is only the continuous rms power delivered. I guess what you are actually getting at is the power-reserves that is there on demand and this is in plenty in the Shindo you are talking about. Did I understand it correctly?
Let me then ask (Cranky, I am actually reading the stuff, but not done yet, and cannot resist asking this), can one design a SS amp at 12 wpc with similar reserves of power? It is probably not done usually, but if one wanted, is there anything in principle against?