Hello @teboerio
This is an interesting discussion. Thanks for sharing.
My rule of thumb for loudness is:
+3 dB = doubles the acoustic power, but sounds only slightly louder.
+10 dB = sounds about twice as loud to most listeners.
+20 dB = sounds about 4× as loud.
+30 dB = sounds about 8× as loud.
Regarding the MA-252, I am not exactly sure why that is. I would ask the manufacturer for details. You can share my reference with them, and their engineers can get back to you about exactly how much louder they intended it be/sound past 52.
Good luck with this.
