Directional pinna for microphone

The outer part of the human ear, called the pinna, has a complex shape containing many folds. It selectively amplifies and attenuates different sound frequencies depending on which direction the sound is coming from. This, combined with information about the volume and timing of sounds reaching each ear, allows the brain to pinpoint the direction the sound is coming from.

This thing is a design intended to provide similar directional sensitivity to a microphone. The spiral ridge along the ins