Hearing loss caused by loud noises is called noise-induced hearing loss (acoustic trauma). It is more common for gradual hearing loss to occur from long-term (chronic) exposure to loud noise than from a sudden (acute) loud burst of sound. Hearing loss may be temporary or permanent. Long-term exposure to loud noises can cause permanent hearing loss.
Common causes of acoustic trauma include:
Most people stop hearing high-frequency sounds, such as bells and chimes, first. Later, it becomes harder to hear lower-frequency sounds, such as voices.
WebMD Medical Reference from Healthwise