Spatial Audio (also called 3D audio) is an audio technology that creates more immersive soundscapes. This frequently involves the virtual placement of sound sources anywhere in three-dimensional space, including behind, above or below the listener. Spatial audio often uses HRTF filters (Head Related Transfer Function), to mimic the way the ears work, and how we would hear a sound in real world environments.
An example of a technique used in spatial audio is ambisonics. Ambisonics is a full-sphere surround sound format. In addition to covering the full 360 degree horizontal plane, it covers sound sources above and below the listener. This is done with special ambisonic microphones and formats. When utilizing ambisonics in a VR environment for example, it enables the listener to turn “within” the sound and hear the sound’s location change depending on the listeners position.
There are many more examples of spatial audio use but the most common exists in interactive media like video games and virtual reality. Other common spatial audio techniques include binaural and surround sound.