Importing ambisonic sounds into Unity: a quick guide

Ambisonic files behave differently from stereo or mono assets the moment they hit Unity's import pipeline, and Unity can't decode them on its own: you need a decoder plugin. Here's how to get them working correctly, in five steps.

1. Confirm your format first

Unity expects ambisonic files in Ambix (ACN/SN3D) B-Format — four channels for first-order (FOA), nine for second-order, sixteen for third-order. If your files were rendered in FuMa format, convert them to Ambix before import; the decoder plugin will not correctly interpret FuMa channel ordering, and you'll get scrambled or collapsed imaging instead of a clean sphere.

2. Install an ambisonic decoder plugin

Unity has no built-in ambisonic decoder. Without a plugin, ambisonic clips can't be decoded at all. Install one via Package Manager before anything else:

• Resonance Audio — free, open-source, solid default choice
• Meta XR Audio SDK — recommended if you're targeting Quest or other Meta XR hardware
• Steam Audio — good option if you're already using it for occlusion/reverb elsewhere in the project

Set your choice under Edit > Project Settings > Audio > Ambisonic Decoder Plugin (and, if you're also spatializing other sources, Spatializer Plugin). These are project-wide settings, so pick before you build out a lot of scenes around them.

3. Set the import settings correctly

Select your ambisonic file in the Project window and check the Inspector:

• Enable Ambisonic in the audio import settings (this checkbox only appears once a decoder plugin is selected in Project Settings)
• Load Type: Streaming for long ambiences, Decompress On Load for short one-shots
• Leave Force To Mono unchecked — obviously, since that defeats the purpose

4. Configure the AudioSource

Drag the clip onto an AudioSource and check Spatialize. This routes the clip through your chosen plugin's decoder instead of Unity's standard panner. Unlike a normal 3D AudioSource, an ambisonic source represents a full soundfield rather than a point emitter — positioning it in the scene affects rotation relative to the listener, not distance attenuation in the usual sense, so don't expect standard falloff curves to behave intuitively.

5. Test rotation, not just playback

The most common mistake: confirming the file plays, then moving on. Ambisonic files need to be tested by rotating the listener (or the AudioSource, depending on your rig) and confirming the soundfield rotates correctly with it. If left-right or front-back imaging flips unexpectedly, it's almost always a channel-ordering or normalization mismatch (Ambix vs. FuMa) rather than a Unity settings problem — go back to step 1.

A note on order

Most real-time decoder plugins for Unity, including Resonance Audio, support first-order ambisonics well. Higher-order (2nd/3rd) support is more limited and plugin-dependent — check your specific plugin's documentation before committing a HOA-based workflow to a mobile or standalone VR target, where CPU budget for decoding is tighter.

Looking for source material to test this workflow with? Grab the free ambisonic starter pack at axisambisoniclab.com and drop a first-order file straight into your scene. Also get the step by step tutorial free here: Import ambisonics in Unity