Google Resonance Audio / Amibsonics rotation

Hi there,
Quick question, how to set up the playback of an ambisonics file so that it rotates correctly with the camera. According to me it sounds like when i turn the camera to the left the ambisonics file rotates to the left, too, while i thought it should turn to the right.
I’ve made a screencast of what I am hearing. You can find it here:
https://1drv.ms/u/s!AkpAk3rcikwr6yGfTXHUDl9x4Fsz?e=a0zm9h

The orange cube contains a mono event spatialised with resonance audio, the green one contains the ambisonics file. Here the settings:


Any ideas of what i should be doing differently? (This also happens without FMOD).

Many thanks for your help and best wishes,
Constantin

If this is happening without FMOD as well, it is possible that this is a quirk with how the Google Resonance and/or Ambisonics are handled in regards to head rotation. It is possible, for example, that the direction the object is “facing” could be affecting the channel swapping. From what I have tested ambisonic files appear to be rotating correctly with both Soundfield and Sound Source plugins.

Could you please check the following:

  • Does this happen within the FMOD Studio application (you can rotate the listener by scrolling the mouse in the 3D preview widget)?
  • Are you game objects oriented correctly (eg. facing the listener)?
  • Is your listener oriented correctly?
  • Are you able to share that specific audio file here for us to test with?

Hi Richard,

Thanks for the suggestions. When I try to rotate the ambisonics file in the FMOD preview widget it rotates correctly. Here the link to the file:
https://1drv.ms/u/s!AkpAk3rcikwr6yyJ51gAoVe6yavu?e=Ed4dn8

In the test scene the object is facing in the same direction as the camera/listener. So the object’s front is aligned with the front of the camera. I wonder if this is where my confusion comes in. The camera sees the objects always from the back, regardless of the distance. For example, if i were to spatialise a mono sound via the Resonance Audio Source and set it’s directivity to 50% I would hear the back of the sound. To hear the front I would have to rotate the object in Unity by 180°. It seems that with playing back ambisonic files it’s the same but with the added confusion that the distance of the object doesn’t matter. One hears the back of the file in the front regardless if it’s in front or behind the camera or if the camera is inside the game-object.

I tried experimenting with the orientations. And all is fine if I also rotate the ambisonics file in a DAW by 180° and rotate the game object by 180°, too. Then, when i rotate the camera the sound aligns with the visuals.

Here the ambiX file where the sound is in the back and plays back correctly when rotated in Unity by 180°: https://1drv.ms/u/s!AkpAk3rcikwr6y2tfrffcTKH5SZb?e=i0xIv7.

Thanks for suggesting double checking the orientations. This has helped me. :smiley:

Best wishes,
Constantin

1 Like