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vbap2D spread behavior

Spat
#1

Hi,

Having used for quite some time old legacy vbap external, I want to replace it with spat.pansig~ as I need audio control of vbap’s parameters.

In the process I noticed that the spread parameter has a really different behavior in spat.pansig~ as compared to vbap. Is this expected ?

Note that in the example below I used spat.pan for demo purpose, but spat.pansig~ give same results

Thanks in advance

Julien

  
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#2

Hi Julien,

Well, yes, the spread law in spat pan is somehow different from legacy vbap external.
Is that really a problem ? Spat pan was not intended to be a one-to-one replacement of legacy vbap.

Anyway, in future versions I might add an option to chose among various spread laws (including the legacy vbap).

T.

#3

Hi,

Thanks for this confirmation. I wasn’t sure whether it was supposed to be an implementation of Ville Pulkki external or not.

Well, it is a problem in my own case, but I must say I’m not using vbap for spatialization purpose, here: I use it in a synthesis patch for scanning some audio inputs and legacy vbap’s kind of bandpass filter-like shape is what I’m interested by. Hence, spat’s spread law inducing more of a balance between between front and rear doesn’t sound very well here. But, yes, that’s quite a specific use case.

I, for one, would be happy to have different spread laws to experiment with ! I’ll also dig some other solutions for my purpose.

Cheers,
Julien

#4

I’ll integrate various laws in future versions.

In the meanwhile, you can also create your own spread law, just as a patch:
Spreading is typically achieved by creating multiple replicas of the virtual source, with varying angles of arrival.
You could combine one or several spat.pan to build such a “multiple-directions” system. Shouldn’t be too difficult.

T.

#5

Hi,

Thanks for your reply and for considering this. Yes, in the mean time I’ll experiment with implementing this by hand.

Cheers,
Julien