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Source center position issue

Hi there

I searched around the forum but I couldn’t find anything related to this issue.

I have a spat5.hoa.encoder in 3rd order that feeds an hoa.decoder to a quad system.

I have one source, and when I place it at coordinates xyz 0.0.0 I would like it to sound even out from every loudspeaker. right now, if I place it in the middle two channels sound louder than the others.

Does it makes sense?

I’m afraid I can’t post the code here as it’s under NDA.


Hi Axel,

HOA (in general) and spat5.hoa.encoder do not account for the source distance. Only azimuth and elevation are actually used. Therefore using a distance of 0 won’t work.

What you could try, however, is to enable the recently introduced “divergence” factor – see spat5.pan~ help patch, “spread” tab. This will spread out the signal, in such a way that loudspeakers are (almost) evenly fed when the source is close to (0,0,0).

NB : not sure if hoa encoder/decoder are super well suited for a quad system, especially with 3rd order…


Hi T.

thanks for the quick response. I’m gonna give a try with divergence, and what about spread then?

I decided to go for 3OA as I have to decode for multiple systems using the same stream, and I found this the easiest solution really.