Spatial audio over AirPlay could be a game changer for Dolby Atmos

Though it was never mentioned during the Worldwide Developers Conference (WWDC) 2024 keynote, Apple will add a very cool new feature to its AirPlay streaming technology in the fall: support for spatial audio.

As spotted by What Hi-Fi, the addition of spatial audio to AirPlay was practically a footnote, appearing at the very end of the Apple’s press release detailing its tvOS 18-based home entertainment enhancements.

The news could be a big deal for anyone who wants to hear spatial audio content, like Dolby Atmos Music, from a compatible wireless speaker. Though it may seem counterintuitive, even though AirPlay currently lets you stream any audio from an iPhone, iPad, or Mac to an AirPlay-enabled speaker, there are still limitations. For instance, AirPlay only supports up to CD-quality, 16-bit/44.1kHz lossless audio — it doesn’t work with any hi-res audio sample rates or bit depths. And if you try to stream Dolby Atmos, say, from Apple Music — even if you stream it to a Dolby Atmos speaker like the Sonos Era 300 — that audio will be down-mixed to stereo before it ever leaves your Apple device.

This limitation of AirPlay has meant that the only way to get spatial audio to a standalone speaker is directly from the source. In other words, Sonos must access Dolby Atmos streams directly from Apple Music in order for the Sonos Era 300 (or Sonos Arc, or Sonos Beam Gen 2) to play it correctly. The same is true for any other Dolby Atmos-capable speaker.

This can create a challenge for builders of spatial audio speakers. Unless they build a companion app, and add support for direct streaming from every music service that provides Dolby Atmos content, there’s almost no reliable way to get the speaker to play Dolby Atmos as it should sound.

With the addition of spatial audio compatibility to AirPlay, any Dolby Atmos speaker that works with AirPlay will be able to receive Atmos wirelessly from any Apple device — regardless of the streaming app in use.

The impact on the audio world could be significant. Audio companies that have been resisting the idea of making a Dolby Atmos speaker now have a major roadblock out of their way. And as the speaker ecosystem responds with more Atmos-capable products, recording artists and music streaming services will respond with more and more spatial audio content.

Unfortunately, since AirPlay remains an Apple device exclusive, we still need a solution for Android and Windows. Adding spatial audio support to Chromecast would address part of this problem. A much better (and more universal) solution would be for the entire industry to throw its weight behind Matter Casting, a open-source alternative to both AirPlay and Chromecast. Once Matter Casting works with spatial audio, we’ll be able to stream any audio from any device to any other device.