The perception of sound as coming from left/right, above/below, and front/back.

Examples:

• When our phone rings while we’re in the next room, we are able to locate it by being able to perceive the direction of the sound.
• In the Microsoft Independence Day Project (a system for vision-impaired users to navigate using a 3D-soundscape), while it’s navigating you around the city, relevant information will sound like it’s coming from a specific direction. For example, information about a store on your left will sound like it’s coming from you left side.

Orientational:

Direction cues obvious have orientational implications. It’s commonly used today to create immersive experiences through things like surround sound or by having certain elements play on certain side of left/right speakers.

Direction is often related to distance.

Metaphorical:

Directional sound creates the illusion of space that might not necessarily be there. It has the potential to create an environment when there is none.

Performative:

The direction of sound might influence us to literally act in a different direction (turn to look or walk towards).

Doppler effect caused by direction & distance