Spatial audio is sound designed to seem like it comes from positions around and above the listener, rather than from a left-right stereo pair, using surround speaker layouts, object-based formats such as Dolby Atmos, or processing for headphones.
It is a relatively new layer in the process described in the music production guide. StereoVision is an independent informational site and is not affiliated with Dolby, any streaming service, hardware maker or studio.
From mono and stereo to surround
Recorded sound has gradually added dimensions. Mono uses a single channel, so all sound comes from one place. Stereo uses two channels, which lets engineers place sounds across a line between the speakers and creates the impression of a stage in front of the listener. Surround sound adds more channels around the room, typically speakers behind and beside the listener, so that effects and ambience can come from the sides and rear.
Cinema was the main home of surround sound, where it helped place dialogue, music and effects in the room. Home theater then brought multi-speaker layouts into living rooms, and music producers experimented with surround mixes for a niche audience. The idea was always the same: use more speakers to build a larger, more enveloping sound picture.
These systems are channel-based. Each channel is a separate signal sent to a specific speaker in a fixed layout, so the mix is made for that layout. A mix prepared for one arrangement of speakers will not automatically suit another, and the playback system must match the way the mix was made, or an approximation must be created.
Object-based audio and Dolby Atmos
Object-based audio changes the approach. Rather than assigning each sound to a fixed channel, the mixer treats a sound as an object with a position in a three-dimensional space, and the playback system works out which speakers to use to place it there. The same mix can then adapt to different speaker setups, from a large cinema to a soundbar to headphones.
Dolby Atmos is the best-known system of this kind. Dolby describes it on its official site as having reinvented how entertainment is created and experienced, allowing creatives everywhere to place each sound exactly where they want it to go, for a more realistic and immersive audio experience, according to the Dolby Atmos official page. Height is a key addition: sounds can come from above as well as around the listener, which adds a dimension that flat surround layouts lack.
For music, Dolby describes Dolby Atmos Music on its professional site as an immersive music experience that adds more space, clarity, and depth to your music, in the wording of the Dolby Professional Music page. Other companies and formats offer comparable approaches, and the details of each differ, but the principle of placing sounds as objects in space is shared.
Spatial audio on headphones
Most people listen on headphones, where there are only two drivers, one for each ear. Spatial audio for headphones uses binaural processing: the system applies filters that mimic how the head, ears and torso change sound arriving from different directions, so the brain perceives the sound as outside the head. The result is an impression of space created from just two channels.
The effect depends on the listener.
Because headphone playback is a conversion from a larger mix, the quality of the conversion matters. A good spatial mix is checked in the format it will be heard in, and engineers often listen on headphones during the work, not only on a speaker array, to make sure the result is convincing.
How spatial mixes are made
Creating a spatial mix is a distinct craft. The mixer starts with the individual elements of a song or a film soundtrack and decides where each should sit: a lead vocal that stays near the center, backing parts that move around the listener, ambience that spreads overhead, an effect that travels across the room. Good spatial mixing serves the music or story and avoids movement for its own sake.
Film has used these tools longest. Sound designers and re-recording mixers place dialogue, effects and score to support the picture, and the way composers write and record music for the screen affects how it can be positioned, a subject covered in the guide to how film scores are made.
Music mixed for spatial formats is usually also released as a stereo version. The stereo mix remains the baseline for most listeners, and a spatial version is an additional release for those with compatible equipment or services.
Mastering, delivery and what listeners need
A spatial mix has its own final checks, in the same way a stereo song is mastered. Engineers verify that the mix translates across playback methods, that levels are consistent and that the delivered files meet each platform’s technical requirements. The principles of final polish and checking are explained in the guide to what is music mastering, though the tools and standards for immersive formats differ from those for stereo.
To hear spatial audio properly, listeners need compatible content and compatible playback. That may mean a streaming service that offers spatial versions, a device that supports the format and either a speaker system with the right layout or headphones with spatial processing turned on. Without the right chain, the content may simply fall back to a standard stereo version.
Standards, products and services in this area change often, so details such as supported devices and available catalogs are best checked on the official pages of the platforms involved.
For creators, the practical question is whether the extra work suits the project. A spatial mix takes additional time and skill, and the audience able to hear it properly is smaller than the stereo audience, so artists and labels weigh the cost against the benefit. Projects built around atmosphere, such as ambient music, film scores and concept albums, often gain the most from the added space.
Frequently asked questions
Is spatial audio the same as surround sound?
Show answer
Surround sound is a channel-based form of spatial sound with speakers around the listener. Spatial audio is a broader term that also includes object-based formats and headphone processing.
Do I need special headphones?
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Not usually.
What is an audio object?
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An audio object is a sound with a defined position in three-dimensional space. The playback system decides which speakers or processing to use to place it there.
Does spatial audio always sound better?
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Not necessarily.
