Why can I not record ambisonics in Unity with Google Resonance?

Question

I've set up Unity (2018.4.0f1 LTS) with the Google Resonance project and I'm attempting to record an ambisonic environment with the Resonance Audio Listener component - however on hitting Record, instead, I get the following error,

Failed to start soundfield recording. UnityEngine.Debug:LogError(Object) ResonanceAudioListener:StartSoundfieldRecorder() (at Assets/ResonanceAudio/Scripts/ResonanceAudioListener.cs:121) ResonanceAudioListenerEditor:OnInspectorGUI() (at Assets/ResonanceAudio/Editor/ResonanceAudioListenerEditor.cs:108) UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

I've spent some time poking through the included scripts and as far as I can see the problem is located in one of the included .dlls, so I don't think I can diagnose it myself.

Kinda desperate for a solution, here, folks, as I have a very close deadline that depends on making an ambisonic recording of the experience I've built.

I should mention that I'm not much of a sound guy, I'm just trying to facilitate the sound guy on our team... =D

Answer 1

Recording Ambisonic A-Format audio is a fairly specialised task which should be undertaken by someone with experience in that particular field.

You need a 4-channel field recorder with identical gain and phase structures across all 4 channels in order to record the 4-channel 1st order A Format signal. There are not many recording devices that are suitable for this.

I would not recommend trying to record this directly into a computer as the audio interface that is likely going to end up being used will not have the gain-structure linking required for this to be effective.

Devices like the SD-788, SD-644, SD-688, Zoom F8n, Zoom F4n, SD-Mixpre, Zoom-F6 are all suitable.

Once the A-Format signal has been acquired it will need to be converted to B-Format Ambix or Fuma format. This is performed using a processing tool that is specific for each ambisonic mic. Once you have it in B-Format, you can start applying it inside of Unity. Processing is normally performed inside a DAW.