Its like comparing the horse power of a lawn mower to a motor cycle. The number can be the same on paper but the end product is nothin alike.
Yeah… I agree that my John Dear mower is nothing like a Kawasaki motorcycle. They are both green, and have engines, but after that…
James Watt, who coincidentally standardised the unit of Horse Power, later the “metric horse” became labeled as being Watts and kilowatts…
So to claim that a watt is not a watt, only means something in the context of asking a two different 1W amplifiers to give 2 watts… and how they clip.
I quest that the OP likes it quiet. The average person needs the 50W amp that the manufacturer recommends. And there is another Gaussian tail of people on the right, that will blow the speaker apart. We can call these the 65dB, 85dB and 105 dB groups… or the A, B and D groups.