How does sound damage ears?

Loud sounds experienced frequently over a long time damage the ear, or rather, the hearing, by destroying the hair cells in the inner ear. Since the hair cells are what convert pressure waves into nerve impulses, if they are damaged, sound is not converted into a signal that can be sent to the brain.

In addition, short sharp, very loud sound can rupture the ear drum and result in temporary or permanent damage that may also impact the ability to hear sound.