Is there something like modulation rate/depth in natural reverberation?

[frenchboy]

If so what causes it?

[valhallasound]

There has been some debate about this. The best statement that I have heard on this is that temperature variations in the air will cause the speed of sound to be different paths, which will cause time variation. HOWEVER, this type of variation doesn't cause pitch shifts. Just time varying phase shifts. It is closest to multipath fading, or Rayleigh fading:

http://en.wikipedia.org/wiki/Rayleigh_fading

The pitch variation I use in ValhallaRoom, ValhallaShimmer, ValhallaÜberMod, and most of the VintageVerb algorithms doesn't really have a physical analogy. The closest thing to multipath fading would be the early reflections in the VintageVerb Ambience algorithm, or the Random Hall and Smooth Random* algorithm.

So, why do I use pitch variation, as opposed to multipath fading? I feel that pitch variation is a better way of simulating the higher modal densities found in large enclosed spaces. Subtle pitch modulation results in a "blurred" perception of the resonance density.

Plus, it just sounds awesome, especially with synths.

Sean Costello

* Smooth Random is part of the upcoming VintageVerb update.

[Sendy]

* Smooth Random is part of the upcoming VintageVerb update.

Well this thread got interesting quickly