Unlocking the Power of Spatialized Audio with Apple Airpods (Spatialize)

Apple’s Spatialize Stereo takes ordinary two-channel audio and folds it into a virtual surround field over headphones. It works with anything you play, including apps that never shipped a spatial format. This article explains what the switch actually does, when it helps, and when it mostly just makes things louder.

For Apple’s broader take on the technology, check out the guide on Apple Spatial Audio.

How this article was made: the first draft came out of an AI, and the result was mediocre — these systems do not really check technical detail on a topic like 3D audio, which is good news for me. I rewrote it completely against my own measurements and productions. Every technical claim below has been checked by a working sound engineer.

What is Spatialize Stereo on AirPods? For the headphone side of the same question, see headphones with spatial audio and Dolby Atmos.

Spatialize Stereo is an upmix. It takes a normal stereo track, applies HRTF filters, and places the result around your head instead of inside it. It needs no Dolby Atmos file and no special release. It runs in two modes, fixed or head tracked, and turning it off simply returns you to plain stereo.

That is the short answer. The longer one matters more, because the three states behave very differently depending on what you are listening to.

Fixed, head tracked or off: which setting to use

The rule behind the table is the degree of freedom the content was made for. Music and film are made to be heard from one position — zero degrees of freedom. You are not supposed to move your head, and while head tracking can be switched on, it adds little. Three degrees of freedom is where the position change is intended: spatial videos, 180° and above all 360° video.

For film I side with Dolby. Watching Disney+ with AirPods Pro connected genuinely surprised me — the centre moved with the picture, the sound felt like it came from outside the earbuds, and that made sense because the screen was in front of me. Voices being head tracked was completely fine there.

Music is where it falls apart. In Apple Music the singer traditionally sits in the centre, along with snare and bass drum. Turn your head and you hear very clearly that voice and instruments come from one direction only. The envelopment collapses. Why should the singer move around, when you cannot even see them?

It is basically an algorithm comparable to 8D Audio. It is not to be confused with what Dolby Atmos does, since Dolby Atmos tracks carry real multichannel audio.

Android caught up on compatible hardware with the Pixel Buds Pro and Samsung Buds Pro 2. Find all spatial audio compatible headphones here.

How Spatialize Stereo works

HRTF stands for Head Related Transfer Function — the filter that describes how your head, shoulders and outer ears colour a sound before it reaches your eardrum. Apply that filter to a stereo signal and the brain reads the result as coming from a direction rather than from the driver.

Sounds become objects that can move over time instead of static points, and the rendering happens in real time on the device. That is the mechanism. Whether it sounds good is a separate question, and it depends entirely on the material.

Even a genuine Atmos music release does not promise a good experience. It comes down to the audio work behind it — which is what I do for a living.

Does Spatialize Stereo actually sound better?

Partly, and less than the demo suggests. When you flip the switch from stereo to Dolby, the audio also gets louder — in my measurements by roughly three volume steps. You do hear more channels, but a good share of the “wow, what is that” comes from the added loudness. Matched for level, the difference shrinks dramatically.

This matters because almost every comparison you will read online was done by toggling that switch. Louder reads as better to the human ear, every time. If you want to judge the format rather than the level, match the loudness first.

Comparing Spatialize Stereo to Spatial Audio

Spatial Audio on Apple devices relies on Dolby Atmos tracks. The signal processing handles not just two channels but multichannel formats such as 5.1 or AC-4, with each channel holding a fixed position in space that head movement then references.

Spatialize Stereo creates an enveloping effect without requiring an Atmos file at all. You enable the switch and get a wider field from material that was never made for it. Spatialize Stereo tries to recreate how humans perceive sound, so it is worth reading my article on binaural audio alongside this one.

Key differences

Both produce a 3D effect over headphones. Apple’s implementation is optimised for specific AirPods and Beats models and enables dynamic head tracking on those. Dolby Atmos carries more information and offers more control at the production end. Spatialize Stereo is the more versatile of the two simply because it works with any source.

Head tracking beats a personalised HRTF

If you only change one setting, change this one. Personalised HRTF fine-tunes localisation. Head tracking has the far larger effect on perceived realism, because without it sounds stay fixed to your head instead of to the room, which feels wrong and multiplies front-back confusions. Your brain expects small positional changes when you move; give it those and it forgives an HRTF that does not fit you perfectly. The reverse is not true — a perfect HRTF does not rescue a static field.

That runs against how the industry markets these products, which lead with ear scans. The scan is the smaller lever.

There is a second contradiction on Apple’s side, and it is worth knowing before you spend an evening toggling settings. Apple supports dynamic head tracking on Apple Music and put it front and centre in the AirPods marketing. But the Dolby Atmos Music catalogue was mixed without head tracking in mind. The feature and the material were built on different assumptions, and you hear it.

The same goes for the labelling. There is an Apple Music playlist promising titles “made for spatial audio”. Going through it, most of the artists and tracks were long familiar to me — they already had a solid stereo mix. The slogan is simply not accurate. I say it reluctantly, but you could call that misleading advertising.

Your listening situation decides the rest. Sitting at a desk with your head more or less still, head tracking makes sense. Walking the dog, most people switch it off so the field stops swinging around. There is more on this in head tracking, so click here.

Setting up Spatialize Stereo on your Apple device

You need compatible hardware, and then it is a matter of a few taps. Connect AirPods or Beats to your iPhone and the option appears in the settings.

Pick an app that supports it, such as Apple Music. I have listed applications with spatial audio content in this 3D audio App overview.

You do not need the newest headphones. There are several ways to get there, and I put together an overview of spatial audio content you can experience at home without hunting for Dolby Atmos tracks.

Enabling the setting

Press and hold the volume slider in Control Center while audio is playing. This is supported by AirPods Pro, AirPods Max and Beats Fit Pro with a compatible iPad, iPhone or Mac.

In Apple Music, Dolby Atmos has to be set to “Always On” if you want the processing regardless of which headphones are connected.

Personalising it

Open Settings and find Personalized Spatial Audio. It will ask you to photograph your ears. It does improve how precisely you can place a sound source — just remember it is the smaller of the two levers.

Where it earns its keep

The honest version: this technology helps most where the content was built with movement in mind, and least where it was not.

Film and TV are the clearest win. Sound direction, distance and height give the picture a room, and the screen anchors everything so head tracking has a reference. I tried it with AirPods Pro and was surprised how well the externalisation held up — less like headphones, more like a cinema where I controlled the volume. Despite the hard time I give Dolby elsewhere, this worked.

Gaming benefits for the same reason: the player moves, so the field moving with them is the point rather than a side effect.

Music is the weakest case, for the reason above. Apple Music is a consumer format and doesn't even sound as good as you can read here. There is real opportunity in material that is not purely entertainment, where a spatial arrangement carries meaning that stereo could not.

A format where head tracking earns it: the radio play

Merkelphone is the clearest example I have produced. A radio play with head tracking from episode one, listenable on AirPods Pro or Galaxy Buds Pro, where turning your head lets you follow the voices. Five episodes, 70 minutes in total, a year of experimenting and recording, released free on five platforms including Spotify and Apple Podcasts. From 2022 a dedicated app added the interactive version.

It works because the format was built for it. Eyes closed, actors moving around you, no picture competing for your attention — the movement carries the story instead of decorating it.

Spatialize Stereo on third-party devices and services

It is not restricted to Apple hardware. Third-party headphones and streaming services can take part.

Third-party hardware

AirPods Max and Pro give the most complete version, since head tracking is built in. Non-Apple headphones still get the processing through Apple Music with Dolby Atmos set to “Always On” — you lose the head tracking, not the spatialisation.

Worth separating two things that sound identical in marketing copy. Galaxy Buds do not deliver 3D audio in the sense of a 360° field: it is not the enveloping sound the AirPods produce, and the advantages of multichannel surround go unused. Their strength is the opposite one — the virtualisation works on everything you throw at it, regardless of source. Two different promises, and which one you want depends on whether you care about envelopment or about coverage.

Streaming services

Netflix, Disney+, HBO Max and Apple TV+ all support it. Check the sound settings of the platform you are using; the option is usually there rather than in the system settings.

Frequently asked questions

What does Spatialize Stereo do?

It converts a stereo mix into a virtual surround field over headphones. Because it works on the input signal rather than a special file, you can use it with apps that do not support spatial audio at all, including Spotify. Read more on what 3D audio Spotify has to offer.

Should Spatialize Stereo be on or off?

Turn it on for film, TV and 360° video, where the picture gives the sound a reference point. Turn it off for music and for any critical listening. If you keep it on for music, use fixed rather than head tracked — a singer who moves when you turn your head breaks the illusion rather than building it.

What is the difference between fixed and head tracked?

Fixed anchors the sound field to your device, so it stays put no matter how you move. Head tracked anchors it to the screen, so turning your head moves you within the scene. Fixed suits music and walking around. Head tracked suits film, 360° video and anything made for movement.

What does Spatialize Stereo mean on AirPods Pro?

You get the full version: the upmix plus dynamic head tracking. In Control Center you can switch the function off entirely, run it fixed, or enable head tracking for stereo and for Dolby Atmos content separately.

Still not sure which setting fits your material?

That is usually a production question rather than a settings question. Let’s look at your project together.