Many consumer headphones have "bloated" bass that muddy the vocals. An EQ can "cut" those frequencies to bring back clarity.
While boosting frequencies can improve your experience, experts from The House of Marley warn against excessively high settings. Pushing digital gain too far can cause (distortion) and potentially damage your headphone drivers or your hearing if not managed carefully. Sound Booster & Music Equalizer" App Analytics - ASOTools equalizer app
Specific settings designed to correct the frequency response of particular headphones or speakers. Top Equalizer Apps for Every Platform Many consumer headphones have "bloated" bass that muddy