I'd agree that tubes seem to put out more power than SS given the same output rating. But I think this has something to do with the way tubes clip and distort vs. the way SS clips and distorts. I think the latter is much more difficult to endure, whereas tubes tend to clip much 'softer' if you will. On a scope the difference is that between a gradual sloping curve and a dramatic, Wiley Coyote cliff, dropping off into an abyss of ear-piercing distortion. (Can you tell I prefer tubes?). The bottom line is that for the same power amp you may be able to push the tubes louder without perceiving (being bothered by) the distrotion/clipping that is actually ocurring.
Marco
Marco