There are few cases where larger amplifiers will sound better, all other things being equal. The disclaimer is important, since there are so many variables in amplifier design. The 'first watt' concept has a lot of credibility, since in many cases the amplifier will be making less than a watt most of the time. Most of the power is used on peaks.
In tube amplifiers the size of the output transformer is paramount. The issue is getting full bass performance vs HF performance. This is challenging and you can assume that any high powered transformer-coupled tube amplifier will have limited bandwidth.
With SETs this issue is even more pronounced and is why the ones that are 7 watts or less are also considered the best sounding. Time was that the 300b was King, 5-7 years ago the 2A3 took ascendancy (about 3.5 watts) and nowadays you hear an awful lot about 45-based amplifiers (maybe about 1 watt).
OTLs do not have this issue; IMO/IME the bigger you make them they better they sound. As far as I can tell this is the only amplifier technology for which it is true that bigger is better.
With transistor amplifiers the issue is all the paralleled devices, which will 'hog' current to a much greater degree than paralleled tubes will. Thus its pretty much mandatory that in a larger power amplifier, all the output devices are matched. Another issue you get into with larger power amplifiers is the extreme levels of negative feedback that are employed- such designs rarely bring home the bacon insofar as the rules of human hearing are concerned.
All this points to the efficiency of the loudspeaker as being quite important overall- since truly musical high powered amplifiers are nearly oxymoronic in general, one will always be challenged to get low efficiency speakers to sound like real music.
In tube amplifiers the size of the output transformer is paramount. The issue is getting full bass performance vs HF performance. This is challenging and you can assume that any high powered transformer-coupled tube amplifier will have limited bandwidth.
With SETs this issue is even more pronounced and is why the ones that are 7 watts or less are also considered the best sounding. Time was that the 300b was King, 5-7 years ago the 2A3 took ascendancy (about 3.5 watts) and nowadays you hear an awful lot about 45-based amplifiers (maybe about 1 watt).
OTLs do not have this issue; IMO/IME the bigger you make them they better they sound. As far as I can tell this is the only amplifier technology for which it is true that bigger is better.
With transistor amplifiers the issue is all the paralleled devices, which will 'hog' current to a much greater degree than paralleled tubes will. Thus its pretty much mandatory that in a larger power amplifier, all the output devices are matched. Another issue you get into with larger power amplifiers is the extreme levels of negative feedback that are employed- such designs rarely bring home the bacon insofar as the rules of human hearing are concerned.
All this points to the efficiency of the loudspeaker as being quite important overall- since truly musical high powered amplifiers are nearly oxymoronic in general, one will always be challenged to get low efficiency speakers to sound like real music.