Apple’s spatial audio is an evolution of surround sound, creating an interactive and dynamic soundscape to bring music, television and movies to life. From iOS 15 , Apple Music makes this feature even more engaging with head tracking on compatible headphones.
So how is it used and can it live up to the hype?
What is spatial audio?
Spatial audio is a new way to experience audio that uses a combination of sensors and gyroscopes in your headphones along with a surround sound audio source to build a virtual 3D space.
If you move your head while listening to standard stereo audio, the sound moves with you. With spatial audio, channels stay where they are as if you’re standing in a surround sound booth with speakers all around you. In TV shows and movies, spatial audio can be used to ensure that the “center channel” (that is, your television or iPad ) stay in the same position, even if you turn your head.
The technology works with standard 5.1 and 7.1 surround sound mixes, but sounds better when paired with newer formats like Dolby Atmos (particularly for music). Where a standard surround sound mix could use five or seven main channels and a stereo recording would use two, Dolby Atmos uses 128 channels to give producers and sound directors much more room to play.
To be clear, Dolby Atmos and Apple’s spatial audio are two separate technologies. Atmos is a format surround sound that can be used convincingly with spatial audio features like head tracking. The new Dolby format has all kinds of benefits outside of spatialized audio, such as in soundbars and home theater setups that don’t rely on headphones.
What devices and headphones support spatial audio?
At present, a iPhone 7 or later and the 12.9-inch iPad Pro (3rd generation or later), 11-inch iPad Pro, iPad Air (3rd generation or later), iPad (6th generation or later), and iPad mini (5th generation) support the function. IOS 14 is required for spatial audio to work, but head tracking for Apple Music is limited to iOS 15 and later.
In addition to a compatible device and sound source, you will also need headphones that can take advantage of head tracking. Currently, only AirPods Pro and AirPods Max are supported. While other headphones support Dolby Atmos (including the original AirPods), not all have the gyros and sensors necessary for head tracking.
You can use head-tracking headphones compatible with an Apple TV running tvOS 15 to take advantage of the feature in video content. Simply pair your AirPods Pro or AirPods Max and watch movies or TV shows from a compatible source like Disney + or Apple TV.
What services support spatial audio?
While many services are adding support for Dolby Atmos (such as the high resolution streaming service TIDAL ), only Apple Music has made headway in implementing spatial audio with head tracking at this time. Apple Music has already made a few thousand Dolby Atmos recordings available, and iOS 15 adds spatial audio head tracking to take advantage of those extra channels.
There are dedicated playlists for music with native spatial audio support, with a dedicated “Now In Spatial Audio” section on the Browse tab in Apple Music. There is a nice mix of old tracks that have been remastered on Atmos and new music that has been produced from scratch in the format.
The feature is also useful for watching movies and TV shows, with services like Disney +, HBO Max, Hulu, Discovery +, Paramount +, Apple TV, and Vudu offering spatial audio on surround sound broadcasts.
How it sounds?
Head-tracking spatial audio is quite different from a standard “flat” stereo broadcast, and it won’t always be to everyone’s liking. Generally speaking, mixes feel wider, with more room to breathe compared to stereo. This can make the listening experience less tiring, but it can also lessen the impact of some mixes.
Depending on the music you are listening to, the effect can be subtle or pronounced. On older tracks that have been remastered for the format, like Queen’s “Bohemian Rhapsody” or Jackson 5’s “I Want You Back,” the lead vocals really stand out. By moving your head, you can clearly hear voices coming from a particular direction, and the same is often the case with lead guitar and melodies.
In this sense, it’s a bit like watching a live show where the higher tones feel more directional but the lower rhythm sections reverberate around you. Live music can be one of the best uses of technology, capturing the essence of being surrounded by a crowd.
Modern pop and hip hop tend to take things even further, with directional audio applied to a variety of sounds and frequencies. The opening bars of “Heat Waves” by Glass Animals sound like the music is coming from behind you, creating a striking juxtaposition when the track is triggered correctly.
Unfortunately, it doesn’t work well everywhere and will not appeal to purists. Some tracks, like the Guns N ‘Roses remastering of Atmos’ Welcome to the Jungle «, they lack punch compared to flat stereo mix. You might want a track like this to sound like you have your face pressed against the PA at a stadium show, but on Atmos it sounds more like a bad car stereo. This isn’t necessarily a gender issue, as Sublime’s “Santeria” sounds great, like you’re sitting in a dirty Long Beach practice space circa 1992.
Head tracking creates a more dynamic soundscape and possibly more interesting listening environment. But this can change the way music sounds. Not everyone will see this as a good thing. Some tracks that sound almost claustrophobic in stereo are easier to hear in Atmos and also sound less “overproduced”.
Classical music might be the genre where the results are most predictable. It’s the closest thing to being in the orchestra without actually seeing an orchestra, and the results are almost always better than a stereo mix (boring by comparison).
How does head movement and tracking work?
Head tracking is arguably best enjoyed when sitting still. If you are watching a TV show or movie, your device (for example, an iPad) will remain the center channel no matter where you watch. With music, things are a bit different.
If you’re walking outside while listening to head-tracking spatial audio, the music will react to your movement. The good news is that the transmission will correct itself when you’ve looked in the same direction for a few seconds.
If you turn 90º to go around a corner, the audio will gradually adjust a few seconds later so that the direction you are looking in becomes the new “center” position. It takes some getting used to and you can turn it off if you want.
Can you turn it off?
On an iPhone or iPad, you can disable spatial audio through the Control Center. Swipe down from the upper-right corner of the screen (or swipe up on older devices), then tap and hold the Volume slider.
The option to enable or disable Spatial Audio can be found in the lower right corner. You can also access AirPods options in Settings> Bluetooth by tapping the “i” next to your headphones and turning off Spatial Audio.
What does “Spatialize Stereo” do?
Your iPhone and iPad will offer to convert normal stereo audio to spatial audio using the Spatialize Stereo option in the Control Center. You will find this option in the same place that you usually use to enable or disable Spatial Audio.
This feature is a mixed bag. It’s essentially a virtual listening booth with a basic stereo recording built in. While it may make some tracks sound a bit more dynamic and interesting, it’s not a great representation of the original track either. Even a track that has been remastered for Dolby Atmos maintains part of the producer’s intent.
You should turn it on and listen to it to decide for yourself, but the “bad car stereo” analogy we alluded to earlier could apply here as well.
Curious? Try a free trial of Apple Music
If you have the necessary headphones and an iPhone running iOS 15 or later, you can jump in and experience head-tracking spatial audio for yourself via Apple Music. The service has a 30-day free trial and includes access to lossless audio streams for all subscribers (only make sure you can take advantage of lossless audio first).