Yes, the compensation of defects but it must be calculable, do not forget that it's the brain that listens.My guess is that would be the level where the noise and distortion are mostly still smothered by the background noise in a room which may also be the point at which your speakers start to distort more noticeably. Say your room has a background noise of 40db and you play music at 80db then an amp with a SINAD of 40db might sound clean enough and you might enjoy the rolled off bass and treble as too much of those makes your speakers distort. From there the speaker distortion may dominate the sound up to the point where the amp is clipping very badly.
And that the ear has a physiological curve, it's the isosonic line. Which demonstrates that the sensitivity is higher between 1 and 5 kHz. 1200 Hz is about the upper limit of the voice.
All this has been known since the beginning of the last century.
We must be able to quantify all this.