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Spat.oper Source parameters

Spat
#1

Hello,

I’m currently digging into spat5 documentation in order to make a quick review of spat5 tools and I wasn’t able to find much informations about some spat5.oper functions. I was especially looking for the definitions of some parameters in Position/Diffusion/Orientation window of the Source Tab :

  • early shape

  • spread (I guess it is something like apparent source width ?)

  • pan rev

I looked at several helps, references and also at the User Manual (which is very instructive btw) and couldn’t find those informations. It would be great to have some definitions of the GUI’s controls in in spat5.oper reference for instance. (What I mean by “definitions” is some description about what does each knob do in terms of source and room effects).

Many thanks !

Simon

#2

Hello Simon,

Thanks for your message. I will add these to the documentation (reference pages or others).

  • early shape : by default, all early reflections (discrete echoes) have the same amplitude. This corresponds to early shape = 50%.
    When you change this parameter, you change the amplitude distribution of the early echoes.
    When early shape < 50 %, the shortest echoes have a stronger amplitude (and the longest echoes are dimmed).
    When early shape > 50%, the longest echoes have a stronger amplitude.

  • spread : apply some spatial spread / spatial blur to the direct sound.
    When spread is 0, the direct sound is like a point source coming from one given direction.
    When you increase the spread factor, the direct sound comes from multiple directions “spreaded over” the main direction, becoming more “blurry”.
    See also spat5.pan~.maxhelp for further details.

  • pan rev : by default, the late reflections (a.k.a “cluster” in spat dialect) and the late reverb (tail) are fully diffuse (coming from all spatial directions).
    When you increase the “pan rev” parameter, some of the cluster reflections will be panned (similarly to the early reflections), making the reverberation effect more directional (less diffuse).

Hope this helps,
T.

#3

Hello Thibaut,

Many thanks for these details and for the great technical support !

Best regards

Simon