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Speaker layout issue. Planar vs 3D

Hi Thibaut (again).

I have an error message which I can’t explain.

spat5.hoa.decoder~: the loudspeaker setup is planar, which is inappropriate for 3D HOA decoding. The 3D HOA stream is downscaled to 2D.

Here is the bit of the patcher that is causing the problem. I thought the speaker setup calculation was correct. Do you see any issue in particular?
Thank you!


----------begin_max5_patcher----------
1718.3oc6Y0saaaCE9ZmmBBgArabcDkD0O6pjhNzdw5Zv1E6hzh.ZIZGlJS4
QQklth12m9bzWrQdnj+2Jx1J.s.0.QhhhTmy467OymNafy3hGXkNneCcMZvf
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C7eu4rOe1+iOwrJI
-----------end_max5_patcher-----------

Hi again,

Yes, this is a “classical” initialization mistake :
At first, spat5.viewer is initialized with 0 loudspeakers.
Then it receives of message for /speaker/number 16.
spat5.viewer therefore creates 16 speakers, and initialize them with default positions. In that case, it’s a circle of 16 regularly spaced loudspeakers. This is indeed a planar setup, and it causes the error message from spat5.hoa.decoder~.
Later, spat5.viewer receives the actual positions of your 16 speakers. These positions are not planar, and the spat5.hoa.decoder~ should be work properly.

So, the error/warning messages you notice are related to a temporary inappropriate state.

The remedy is to use spat5.viewer @initwith "/speaker/number 16". That should avoid the (spurious) error messages.

Best,
T.