hearing aids

     

A hearing ai is an electroacoustic body-worn apparatus which typically fits in or behind the wearer's ear, and is designed to amplify and modulate sounds for the wearer. Earlier devices, known as an "ear trumpet" or "ear horn", 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.