I'm almost ashamed that a person of your caliber posted this. It is INCORRECT.
Higher frequencies cause far more damage and increase hearing loss as opposed to bass, "air" frequencies.
Higher frequencies from tweeters "break off" the tiny hair folicles in your ear drum increasing the rate for hearing problems. Hence higher frequencies pierce you more.
Bass from subwoofers over time (I at times experience it with the occaisional ringing) can cause damage, but no where near as fast as tweeters do. Bass waves do exactly that to the hair folicles in your ear, they wave; they make them move as though it were a sine wave on a graph or flag flopping in the wind.