A hearing aid is an electroacoustic device which typically fits in or behind the wearer's ear, and is designed to amplify and modulate sound for the wearer. Earlier devices, known as ear trumpets or ear horns, were passive funnel-like amplification cones designed to gather sound energy and direct it into the ear canal. Similar devices include the bone anchored hearing aid, and cochlear implant.
Read more about Hearing Aid: Types, Indications, Adjustment, Purchase Costs, Batteries
Famous quotes containing the words hearing and/or aid:
“Dark night, that from the eye his function takes,
The ear more quick of apprehension makes;
Wherein it doth impair the seeing sense
It pays the hearing double recompense.”
—William Shakespeare (1564–1616)
“Without the aid of prejudice and custom, I should not be able to find my way across the room.”
—William Hazlitt (1778–1830)