The ear is the organ of hearing and, in mammals, balance.In mammals, the ear is usually described as having three parts—the outer ear, the middle ear and the inner ear.The outer ear consists of the pinna and the ear canal.Since the outer ear is the only visible portion of the ear in most animals, the word ear often refers to the external part alone.Amplification of sound by the pinna, tympanic membrane and middle ear causes an increase in level of about 10 to 15 dB in a frequency range of 1.5 kHz to 7 kHz. This amplification is an important factor in inner ear trauma resulting from elevated sound levels.. Nonelectrical hearing apparatuses which were designed to protect hearing (particularly that of musicians and others who work in loud ...
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