I used to drive a Camry where on the factory radio, bass and treble had individual knobs and you could adjust them without taking your eyes off the road. Oh, those were the days.
Some had a whole equalizer: https://hackaday.com/wp-content/uploads/2021/06/btcaraudio-v...
Some had a whole equalizer: https://hackaday.com/wp-content/uploads/2021/06/btcaraudio-v...