Dolby Atmos is safe for now, but Apple is taking spatial audio to the next level with its Apple Spatial Audio Format (ASAF). It plays on most Apple platforms but excels on visionOS.
The new format was introduced not during the WWDC 25 keynote, but in a dedicated developer session.
- "Spatial Audio is as important as video when considering creating a compelling immersive experience. We have created a new format for Spatial Audio called Apple Spatial Audio Format, or ASAF. ASAF is used in production to create truly immersive audio experiences. The Apple Positional Audio Codec, or APAC, is used to encode this audio format for delivery purposes," Blake Gordon, Immersive Video Engineer at Apple, said at WWDC 25.
What is Apple Spatial Audio Format?
If you own newer AirPods you may already have tried watching movies in Dolby Atmos with dynamic head-tracking via Apple TV 4K or iPhone/iPad. It is an impressive experience.
Apple has spent years developing this foundation and is now formalizing it (together with another new initiative that we will cover tomorrow – now online). APAC was standardized in mid-2024, and ASAF was officially announced at WWDC 25 this month.
- "ASAF enables truly externalized audio experiences by ensuring acoustic cues are used to render the audio. It's composed of new metadata coupled with linear PCM, and a powerful new spatial renderer that's built into Apple platforms. It produces high resolution Spatial Audio through numerous point sources and high resolution sound scenes, or higher order ambisonics. The rendered audio is completely adaptive based on the object position and orientation, as well as listener position and orientation. None of it is baked in. And the sounds in ASAF come from all directions in any position, and at any distance," explained Blake Gordon.
In simpler terms, ASAF allows sound to feel as if it exists in real 3D space around you. It adapts in real-time not only to your head movements but also to object positioning, dynamically adjusting things like volume, echo and reverb in a virtual environment.
Apple's Spatial Audio technology brings 3D audio to life
Designed for visionOS
Apple's spatial audio will play on all Apple platforms (tvOS, iOS, iPadOS, macOS, visionOS) except watchOS. It can be authored using Apple AAX plug-ins or DaVinci Resolve Studio, and delivered in an .MP4 container using APAC as the codec (up to 768Kbps bitrate).
However, it will only truly shine on visionOS, where it can utilize real-time head-tracking and positional data from Apple Vision Pro's sensors to precisely match audio to what you are seeing in AR/VR. This is why Apple's own Immersive Video content on Vision Pro sounds just as good as it looks.
At WWDC 25, Apple said that APAC is required for all Immersive Video titles. This does not rule out Dolby Atmos as it can be used within the system.
Also read: First look at Apple Vision Pro: A video revolution
iPhone 16 can capture spatial audio in the new format for playback on Vision Pro or AirPods – independently of Dolby Atmos – but professional equipment is needed for the best result.
The launch of ASAF marks a key step in Apple's ambitions for spatial computing. Expect to hear more about it in the coming years. Now, let us have a more affordable headset.
Apple ASAF and APAC
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