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spat.shoebox for room simulation?

Spat
#1

Hi,

I need to create some realistic 3D audio environments. Not perceptually realistic, but physically realistic - as much as possible -. One key to that is a realistic room simulation. The diffuse part of the spat reverb is definitely sufficient, but I am not sure about the early reflections (they come from only two directions if I am not mistaken).

I saw the spat.shoebox tool. I originally thought it could be used to replace the spat reverb by a room simulation reverb, but if I understood well, it is a tool to show the positions of the source images in a rectangular room, more or less independently of spat.
Is there already a spat function that I could use between the spat.shoebox and spat.spat~ or spat.decoder~ to use it to simulate realistic early reflections? (it would add the wall absorption and avoid the user to have to connect all 128 patch cords)

If not, does it make sense that I design one? I will be limited to 127 reflections for one source, but that’s a start. However, that would not be optimized at all in the sense where the same source would be duplicated many times…

Laurent

#2

Hi Laurent,
in case you haven’t seen it yet, there is an example of how to integrate a shoebox image source model with spat’s late reverb in the spat tutorial #19. If you take a look in the “image-source-model” subpatch you can see there is a spat.receive~ @name reverb_bus which receives the early reflections to be sent to spat.reverb~. Maybe this is the approach you are looking for?

best,
Rama

#3

Hi Rama!

It was exactly what I was looking for, thank you very very much, I had missed this :slight_smile:

Laurent

#4

Hello Laurent,

I’ve been working for several months on the same goal, and I am starting to get something that is close to what I was hopping for, so I confirm that it works pretty well, but you’ll certainly have to rewrite and re-organize the entire spat’s acoustics section to make it work the way you want.

As Rama wrote, you can study the tutorial n° 19 to get an idea of how spat.shoebox works. Also, you can check tutorial n°9: “Patching spat”, cause you will have to understand how spat’s reverb engine is organized in order to be ale to tweak it. Last but not least, spat.oper_ will process a lot of things for you, don’t hesitate to use it ^^

Best regards,
Philippe.

#5

Hello Philippe,

Thank you very much for the tips! Right now, it seems I have quite q bit of hiss at the moment, but I had the same issue with other room simulation softwares. But for now, my patch is just some basic modifications done the the tutorial 19. I’ll dig deeper into it and into tutorial 9, thank you!

Best regards,

Laurent