"You are talking about the end of the road. I'm talking about the difference
between the starting and ending of the road. Relative, not absolute. If I move the starting point further, then add the same delta, the end of the road is extended. That my riddle for now."
sounds like what thy is saying here is that in order to preserve dynamics at a higher level of spl, you have to have what seems like a stupid loud system. it is not stupid loud because the spl that we hear is some form of time averaged spl, not peaks. if you like an average of 85db, 115db peaks in the bass are required, at the listening position, more at the speaker. if, on occasion, you want to go loud and listen up around 95db average, then you need 125db peaks without compression.
the ears have a natural built in protective mechanism. if you turn up the volume slowly, the ear will enter protection mode. as you enter protection mode, the "feeling" of the music is preserved, but the ears don't get damaged (well, maybe a little).
anybody who has ever driven/ridden in an open top car on the highway knows how this works. you are driving down the road when you try to communicate with the passenger/driver. when you speak, you almost can't hear yourself unless you are almost screaming. i measured spl in this environment to be around 95db, but it doesn't seem loud or painful or anything. it just seems "normal" until you try to speak and then realize that you can't hear yourself.
i've frequently played music at full blast while on the highway with a measured spl of about 100db average. it didn't sound painful at all, just a medium-loud fun level. in a quiet room, 70db is just fine for me and full reference is borderline painful.
so what i think thy is saying is that if you listen to loud music, you can find yourself turning it up as the night goes on to the point where it is absolutely blasting, but it won't really sound that loud. in order to keep the music going at such high levels, you need a system that you would think would be beyond overkill.
is that the right answer or do i get fed to the hydra?