SPATIAL AUDIO – week ten
Spatial audio is another term for immersive, 360-degree sound around a listener, which take two forms. These are binaural, which is used in headphones and earbuds, and another form is object-based, used for television, radio and loudspeaker listening. Spatial audio builds upon placing “audio objects” within a 3D space, also taking height into account, allowing sounds to be heard as if they were above or behind you rather than just left or right in stereo. It can also involve head tracking, where the sound also moves depending on where the listener moves their head. To recreate the impression of placement of sounds, the timing of sounds from your left ear to your right ear should be considered. For example, if a sound originates to the left side of you, then your left ear would pick up the sound first, then later your right ear would detect the same sound. With this delay of the sound coming from the left to right ear gives us as the listener an idea of where the sound comes from.
Apple announced spatial audio in 2020, with their take on Dolby Amos for headphones, where Apple spatial audio is designed to showcase surround sound and 3D audio through Apple headphones. They were inspired by 5.1, 7.1 and Dolby Atmos signals, applying directional audio filters, adjusting frequencies in each side of the earphones heard, which can allow them to place sounds within a 3D space. The idea is to recreate the audio experience in a cinema setting, where sounds can appear to be in front of you, left and right, the rear and above you, much more advanced than stereo playback. The way Apple spatial audio tracks head movement is through the use of accelerometers and gyroscopes in Apple headphones to position the sounds accurately. In addition, the position of the listener’s iPhone or iPad is also tracked, where the sound then moves according to where your Apple device is.
BBC Academy (n.d.). Spatial audio: Where do I start? [online] BBC. Available at: [https://www.bbc.com/academy-guides/spatial-audio-where-do-i-start.]
Katz, L. (2023). What is spatial audio and is it worth using? [online] Android Authority. Available at: [https://www.androidauthority.com/what-is-spatial-audio-3188080/.]
Parsons, T. (2021). Apple spatial audio: what is it? How do you get it? And is it like Dolby Atmos? [online] What Hi-Fi. Available at: [https://www.whathifi.com/advice/what-is-apple-spatial-audio.]