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disconnecting reverb from spatialisation

Spat
#1

Hi,

I am interested in using some of the spat modules, but not all of them. Namely, and mostly for the moment, the reverb. Then, the spatialization itself would take place outside the spat. Since some spectral corrections need to be done upstream, are they independent from the spatialization process itself (which would make sense since several spatialisation techniques can be implemented with the spat)?

Thanks

Coralie

#2

Hi Coralie,

As explained in the user manual, the audio processing of Spat is made of 3 main components :

  • the room effect (i.e. reverberation effect),
  • the panning stage (spatialization),
  • the decoding/transcoding stage.

The [spat.spat~] object comes with all these modules already interconnected and ready-to-use (rapidly).
However each module is also available independently, leaving you free to use only the reverb for instance
(this might require more patching efforts though).
Thus, it is possible to build a reverb engine that provides « non-spatialized » signals, and to spatialize them « outside the spat » (how dare you?).
All the « spectral corrections » are applied inside the room stage; not in the panning stage.

Tutorial #9 shows you how the reverb engine is built within Spat (based on [spat.source~], [spat.early~], [spat.cluster~], [spat.reverb~] and a bunch of [spat.hlshelf~] filters). NB : this tuto is not trivial.
Alternatively you can build a simplified reverb based on these objects.

T.

#3

Hi T.

I was precisely using that tuto, and read the documentation before using it. I have reasons to spatialize it differently, which are a little long to explain, and cannot be bypassed :slight_smile:

I guess my question goes a little beyond the scope of use of the spat. It’s tackling the relationship between the different stages of virtual spatialization including room effect, from a technical standpoint.

I saw that the reverb control implies panning. Hence my hesitation. I need to explore the objects a little more, just started today.

Thanks

Coralie

#4

“I saw that the reverb control implies panning.” : what do you mean ?

Regarding the “relationship between the different stages of virtual spatialization including room effect”,
Spat uses the following (basic) model:
the Spat room effect produces 4 temporal segments : direct sound, early reflections, late reflections (aka cluster)
and late reverb (tail). These 4 segments are spatialized as follows:

  • the early reflections “surround” the direct sound. Namely, the early reflections come from 2 directions slightly to the left and to the right of the direct sound.
    (the span between these two spatial reflections can be adjusted with the “early width” parameter)
  • the cluster and late reverb part are spatially diffuse (i.e “uniformly spread” across all available loudspeakers).

This simplistic model is not very realistic, but it has some advantages.
Based on tuto #9, you could build a different room/pan relationship, according to your needs/tastes.

Good exploration,
T.