Experience has shown me that in the single ended class A triode world, a lower powered amplifier generally means better sound than a higher powered amplifier. Will a 50 watt GM70 amplifier outperform a 2 watt 45 ?..... Is that true, what do you guys think, does lower power mean better sound.
To make an obvious point every valve amp will have then tonal signature of the valves used. Valves that have lower output 45, 50, 300b even el84 have a signature that other types don't have. Yet the ultimate result is still dependent on the design and parts used, so while a single ended 50 or 45 may be excellent in theory, the proof is in the listening. The other problem is being able to effectively drive a speaker. Some even more powerful amps don't handle load well, just talk to Pat Turner about this, poor load handling is poor design however. Just look at how his monster valve amps handle load, just about no body declares the real results of what the amp is doing under load. He has had amps in the workshop with good specified power output but under load they reached high distortion figures after only a few watts. The moral here if there is one, is its the amps actual behaviour that matters. If you have two amps one of 3 watts and one of 20 and they both behave well under load then the 20 watt one will have more real world capability.
I agree with Omono there isn't a perfect amp. Maybe the question is better answered, what is the better amp for? If you have efficient high quality speakers and want to play less complex music with a lot of vocals its hard to go past low power triodes. Yet when you have music that has more scale and complexity low power triode amps have their limits, though by going the extra mile in power supply and output transformers etc this can be offset somewhat.
Push pull fog has no place in serious well implemented push pull design. Sure some push pull amps may sound like they are more foggy, that is due in part for designers being concerned with max power output not controlling the other variables involved. On the contrary a well implemented push pull offers superior load handling and has the possibility to be less foggy than a single ended amp. I own both types of amps so I have no vested interest either way. Though steve is responding to what he has heard, and if shortcuts and poor design are event, in his words id imagine what he hears is a foggy amp. Its a design challenge, though is no reason why a well designed push pull amp cant sound real, give up some extra power and run in class A.