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+90° degrees rotation by default on HOA bus


It seems that there is a difference of +90° degrees in yaw on the HOA bus between the panner and the audio decoded. I tried to reproduce a simple session in panoramix with only one mono object to compare the binaural bus and the hoa (routed to a decoder in another software) and there is the same behavior.

To reproduce :

  • Create a mono track on panoramix
  • Create a HOA (3rd order in my case) bus and a binaural bus
  • Route the HOA bus to an external decoder (used reaper with compass_binaural from AALTO and energy visualizer from IEM)
  • Route the mono track to both bus
  • Send audio file to the mono track created and change the azimuth from 0° to -90°

→ the binaural bus decodes as expected and you can hear the source moving to your left
→ at 0° on the HOA bus, you already hear the source from your left then it goes behind you (same behavior on the energy visualizer)

Is there something I’m doing wrong ? I’m on Panoramix 1.5.2 on Windows 10.



Hi Pierre,

There is no issue with the panner and/or decoder.
Just a different convention between Panoramix and the other tools (Aalto, IEM) :
in Spat and Panoramix, the “front” direction is +Y. In Aalto and IEM tools, the front direction is +X. Therefore a 90° difference (in the HOA encoded stream), that is easy to compensate for.


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Ha ! I didn’t remember this, of course :face_with_open_eyes_and_hand_over_mouth:

Thanks for your answer and sorry for the noise,