> I assume that a "psychoacoustic effect" would not harm anyone's hearing, whereas volume - i.e. the measure of energy ouput - would, right? Not quite true. It

> I assume that a "psychoacoustic effect" would not harm anyone's hearing, whereas volume - i.e. the measure of energy ouput - would, right? Not quite true. It’s a psychoacoustic effect because it’s something that can’t be observed outside of someone’s conscience, but that doesn’t mean there isn’t a mechanical component to the effect. Most importantly, the effect almost certainly has a substantial mechanical component that’s determined by how effectively your hearing system can couple sounds from your outer-ear into your inner-ear. Like all mechanical systems it’s transfer function is non-linear, it’s much better at coupling some frequencies that other frequencies. If the compression done to the music is pushing the sound to in a frequency band that’s more strongly coupled, then energy output from the speaker might be the same, but the amount that ends up in your inner ear will increase, bringing with it higher chances of permanent damage.