Pinna
The pinna is the visible part of the ear that resides outside of the head. We often use the pinna, also called the auricle, for hanging earrings and resting eyeglasses, but the primary purpose of the pinna is to collect sound. It does so by acting as a funnel, amplifying the sound and directing it to the ear canal. While passing through the pinna, sound also goes through a filtering process in which sounds in the frequency range where human speech is normally found are enhanced. Finally, the filtering process also adds directional information to the sound.
