How many watts??

If I have a 80 watt stereo amp and I normally listen at quarter volume and never play at levels higher than this. Do I really need 80 watts could I use a 15 watt amp at half volume?

My next question if I have speakers that my mfg states needs min 50 watts to really make them sound good with my current amp rated at 80 watts but played at qtr volume does that mean I am not really getting the best from these speakers. If I play at half volume this is too loud, do I need a bigger room. Sorry if I did not explain clearly enough.

An oscilloscope might tell you what the maximum voltage is you are presenting to the speakers. Once you know that, then you could make an objective decision.

Or just hook up your amp and subjectively determine if it sound good to you.

More information is needed, specifically what are the speaker's rated sensitivity.

It is a hypothetical post or a troll post.
So I am not sure that more information is need? It is either answered generally and hypothetically or it is not.

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.

I can drive an inefficient speaker with 44w/channel and it sounds great too at the 12 o’clock position… (The speakers are 84 or maybe 86 dB/W/1-meter.)
If the OP is playing at 1/4 of the way up, it is not likely that they are playing it at more than 1W, and at that point… then what is the fascination with the speaker’s sensitivity and efficiency?