Psychoacoustics is the psychophysical study of acoustics, it is about how we perceive sound and
“Due to our hearing limits, you may find that high-passing frequencies around 30 Hz brightens a mix by removing unimportant low-end information that is hard to perceive, although this is not always the case. Increasing that filter to 50–60 Hz, while reducing the high-end to 10–12 kHz, will make mixes and instruments sound “lo-fi,” replicating the poor frequency response of old recording technology.”
https://www.izotope.com/en/learn/psychoacoustics-how-perception-influences-music-production.html