Design

Immersive sound

Updated: Mar 2, 2026

Immersive sound offers a dynamic and realistic sound experience. It is a broad topic that encompasses many different aspects of audio. It simulates everyday hearing by using spatial audio technology and accurately modeling room acoustics. This results in a captivating and lifelike connection with the listener. Additionally, the following terms are important building blocks for designing immersive sound into your experiences:

Sound design is the creative process of designing an immersive soundscape that transports your end-user into a captivating audio experience. While a soundscape, is the collection of all the sounds that are heard in a given environment.

Sound mixing is the process of blending sounds together. In linear mediums such as music and movies mixing involves finding the right volume level and panning for each of the tracks, as well setting up reverb. In immersive experiences, mixing is more complex because the soundscape is dynamic and the listener could be in motion.

This page will introduce more high-level concepts related to sound design and best practices for mixing your immersive soundscape.

Differences between immersive and non-immersive sound design

The tools for mixing interactive non-immersive experiences are typically automatic panning based on direction, volume controlled by distance-based curves; and there are a variety of dynamic reverb solutions. In immersive experiences the soundscape is dynamic; the volume level and panning is dependent on the direction and distance of the sounds. Panning is replaced with Head-Related-Transfer-Functions (HRTF) which provides more accurate directional cues than panning. It’s also possible to achieve more accurate distance cues with careful consideration of how the volume changes over distance and how reverb is treated.

Immersive sound design

Audio for non-immersive experiences could be played on systems with low-quality desktop speakers, full surround hi-fi systems, or headphones of varying quality. A consequence of having to support such a broad range of audio systems, is that audio reproduction is very inconsistent, and a primary concern for sound design and mixing is making sure it sounds decent across all systems. Immersive devices could have headphones built-in which provide much more consistent audio reproduction. This, with the addition of head-tracking, allows for much more immersive spatial audio.

It is recommended you follow these best practices:

Properly spatialize sound sources.

Create soundscapes that are neither too dense nor too sparse.

Avoid user fatigue.

Use suitable volume levels comfortable for long-term listening.

Design with appropriate room and environmental effects.

Mono sounds

Most spatialization techniques model sound sources as infinitely small point sources. Sound is treated as if it were coming from a single point in space as opposed to a large area. As a result, most sounds should be authored as monophonic (single channel) sources.

Avoid sine waves

Pure tones such as sine waves lack harmonics or overtones, which present several issues:

Pure tones do not commonly occur in the real world, so they often sound unnatural. This does not mean you should avoid them since many immersive experiences are abstract, but it is worth keeping in mind.

Head related transfer functions (HRTFs) work by filtering frequency content, and since pure tones lack that content, they are difficult to spatialize with HRTFs

Any glitches or discontinuities in the HRTF process will be more audible since there is no additional frequency content to mask the artifacts. A moving sine wave will often bring out the worst in a spatialization implementation.

Use wide spectrum sources

For the same reasons that pure tones are not ideal for spatialization, broad spectrum sounds (such as noise, rushing water, wind sounds) spatialize very effectively providing lots of frequencies for the HRTF to work with. They also help mask audible glitches that result from dynamic changes to HRTFs, pan, and attenuation.

In addition to a broad spectrum of frequencies, ensure that there is significant frequency content above 1500 Hz, since this is used heavily by humans for sound localization. Low frequency sounds are difficult for humans to locate. If a sound is predominantly low frequency (rumbles, drones, shakes, etc.), then you can avoid the overhead of spatialization and use pan/attenuation instead.

Creative control

When it comes to sound design for immersive experiences, realism is not necessarily the end goal. Keep this in mind at all times. As with lighting and effects in computer environments, what is consistent and/or “correct” may not be aesthetically align with your art direction. Audio teams must be careful not to back themselves into a corner by enforcing rigid notions of lifelike accuracy on an immersive experience. This is especially true when considering issues such as dynamic range, attenuation curves, and direct time of arrival.

Accurate 3D positioning of sources

For more traditional mediums, sound is positioned on the horizontal plane with 3D panning. So sound designers working on non-immersive experiences don’t need to concern themselves with the height of sounds, and can simply place sound emitters on the root node of the object. HRTF spatialization provides much more accurate spatial cues, including height, and with this improved accuracy, it is especially noticeable if sound is emanating from the wrong part of a character.

It is important to position the sound emitter at the correct location on a character (e.g. footsteps from the feet, voices from the mouth) to avoid weird phenomena like “crotch steps” or “foot voices”.

Directional sources

Sound source directivity patterns (speakers, human voice, car horns) is an experimental feature in the Meta XR Audio SDK. These parameters are subject to change or removal in future versions of the SDK. However, higher level SDKs often model these using angle-based attenuation that controls the tightness of the direction. This directional attenuation should occur before the spatialization effect.

Volumetric sources

Not all sounds are point sources, the Meta XR Audio Spatializer provides volumetric sound sources to model sounds that need to be more spread out such as waterfalls, rivers, crowds, and so on. This is controlled with the source radius parameter, read more here: Volumetric Sounds.

Doppler effect

The Doppler effect is the apparent change of a sound’s pitch as the source approaches or recedes. Immersive experiences can emulate this by altering the playback based on the relative speed of a sound source and the listener, however, it is very easy to introduce artifacts inadvertently in the process.

The Meta XR Audio Spatializer does not have native support for the Doppler effect, but most sound systems/middleware provide the ability to implement the Doppler effect.

Time of arrival

In the real world, sound takes time to travel, so there is often a noticeable delay between seeing and hearing something. For example, during a thunderstorm you will see lightning flash before you hear the clap of thunder. Modeling time of arrival delay may paradoxically make things seem less realistic, because it introduces additional latency and can make it feel like the sound is out of sync with the visuals.

The Meta XR Audio Spatializer does not have native support for time-of-arrival, but if desired for dramatic effect it can be added to specific sounds (like thunder) by adding a short delay in the sound system/middleware.

Head-locked audio

A great deal of content, such as music, is mixed in stereo. Since immersive experiences use stereo headphones, it’s tempting to play stereo sounds without spatialization. The drawback is these stereo sounds will not be positioned in the virtual world and will not respond to head tracking. This makes the audio sounds appear “head locked”.

Head-locked audio is stereo-mixed audio that remains fixed in the listener’s headspace instead of responding to their position in a virtual world. This can detract from the spatial audio experience and should generally be avoided when possible.

For original compositions it’s best to mix to ambisonics which can be rotated and won’t be headlocked. If that is not an option then try to be mindful of how the music impacts the spatial audio.

Performance

Performance is an important consideration for any real-time application. The Meta XR Audio Spatializer is highly optimized and extremely efficient, but there is some overhead for spatializing sounds compared to traditional 3D panning methods. Even in cases where there is a significant amount of audio processing, it should not impact frame rate because real-time audio systems process audio in a separate thread to the main graphics render thread.

In general you shouldn’t be too limited by performance overhead of spatialization but it’s important to know your audio performance budget and measure performance throughout development.

Latency

While latency affects all aspects of immersive experiences, it is often viewed as a graphical issue. However, audio latency can be disruptive and immersion-breaking as well. Depending on the speed of the host system and the underlying audio layer, the latency from buffer submission to audible output may be as short as 2 ms in high performance PCs using high end, low-latency audio interfaces, or, in the worst case, as long as hundreds of milliseconds.

High system latency becomes an issue as the relative speed between an audio source and the listener’s head increases. In a relatively static scene with a slow-moving viewer, audio latency is harder to detect. You should aim for around 100ms as the threshold where the delay for head rotations is noticeable for most users.

Effects

Use effects including filtering, equalization, distortion, flanging, to enhance the immersive experience. For example, use effects to simulate the following situations:

A low pass filter to emulate an underwater environment, where high frequencies lose energy more quickly than in air

Distortion to simulate disorientation

Sound mixing for immersive experiences

Sound mixing for immersive experiences is a complex subject and there are many factors to consider.

Distance attenuation curves

Controlling the relative levels of each sound is a critical component of mixing, along with how volume attenuates based on the distance between the source and the listener. In non-immersive applications this is usually controlled by distance-based attenuation curves whose shape is tailored by the sound designer.

Make sure important sounds are clearly heard even at a distance, and unimportant sounds don’t clutter the mix. As an example, you don’t want to lose important character dialog because the user is too far away. It may be better for this sort of dialogue to attenuate more slowly, while less essential footsteps from a character in the background should attenuate more quickly, or potentially be inaudible at a certain distance.

When mixing for immersive experiences there is an opportunity for heightened immersion if we provide the correct audio cues, so it’s important to consider how these attenuation curves impact perception of distance. If you have a sound that is loud even when it’s far from the listener, it may feel closer than intended and negatively impact the user’s sense of immersion.

The rule of thumb for physically accurate distance attenuation is: “a doubling of distance is a halving of intensity”. For example if a sound is set to full volume (0dB) when it’s 5 meters away, it would be -6dB when it’s 10 meters away, and -12dB when it’s 20 meters away, and so on.

Note: Sometimes this attenuation model does not produce the desired result, in these cases it’s necessary to bend the laws of physics a little to achieve the desired experience.

Reverb

Apart from volume, another essential distance cue is reverb. When a sound is very far away humans hear a lot more reverb relative to the direct sound, whereas, when a sound is very close our ears hear more of the direct sound and very little reverb.

Controlling the amount of reverb per sound is a critical component to creating the perception of distance.