Room360: Spatial Reverb, Acoustic Sim, Virtual Studio

[jbraner]

2. The walls can indeed be adjusted like that. For each wall, you can adjust both the reflectivity (decided on this instead of absorption, since it's a bit more intuitive for unsophisticated users), and the diffusivity (otherwise known as scattering). The diffusivity is a tricky concept, because it doesn't really make any difference except in the case of impacts/impulses, like drums. In that case, a high diffusivity avoids any "fluttering", and simulates a very random/rough wall surface. In both cases, this is tunable as a function of frequency. So yes, you can achieve a real "morphing room mode" effect by giving different walls different properties. If you place the microphones to the right of a large room, the residual afterglow will sound like it's coming "from the left".

We could really use some "presets" or something though. I, personally, have no idea how to set up a "normal" wood or plasterboard wall. I know we can "use our ears" - but it would be helpful to have a starting point or two

[bmanic]

It's a really nice plugin and reminds me of the old QuickQuack reverb where you could design your own 2D room.

Unfortunately the plugin is badly bugged, at least on Mac in Reaper. If you save a preset, using Reaper's built in system, and then reload it, you keep getting more and more sources added which you have to manually delete. What's worse is that the actual source and position of it saved within the preset can NOT be maintained as the sole source.. it demands it to be deleted and only the magically appearing original source in the original default position is accepted.

Very strange bug and makes the plugin super frustrating to use. My careful tweaks are basically void.

[Room360 Audio]

It's a really nice plugin and reminds me of the old QuickQuack reverb where you could design your own 2D room.

Unfortunately the plugin is badly bugged, at least on Mac in Reaper. If you save a preset, using Reaper's built in system, and then reload it, you keep getting more and more sources added which you have to manually delete. What's worse is that the actual source and position of it saved within the preset can NOT be maintained as the sole source.. it demands it to be deleted and only the magically appearing original source in the original default position is accepted.

Very strange bug and makes the plugin super frustrating to use. My careful tweaks are basically void.

Yes, sorry, I am working in v1.1.0 which will come with a more carefully thought out preset system and eliminate these issues, as well as various other small problems.

[bmanic]

It's a really nice plugin and reminds me of the old QuickQuack reverb where you could design your own 2D room.

Unfortunately the plugin is badly bugged, at least on Mac in Reaper. If you save a preset, using Reaper's built in system, and then reload it, you keep getting more and more sources added which you have to manually delete. What's worse is that the actual source and position of it saved within the preset can NOT be maintained as the sole source.. it demands it to be deleted and only the magically appearing original source in the original default position is accepted.

Very strange bug and makes the plugin super frustrating to use. My careful tweaks are basically void.

Yes, sorry, I am working in v1.1.0 which will come with a more carefully thought out preset system and eliminate these issues, as well as various other small problems.

While you are at it, could you consider adding some modifier key combo with control key that _only_ selects the walls within the selection box and one that _only_ selects the microphones and source. Would make it much easier to operate complex setups. Right now the workaround is to try and shift click sources and microphones, move them out of the way to an empty space, then select all walls.

[DaveClark]

@DaveClark

Sorry, I actually forgot I made this thread. I'm really sorry about that. To answer your questions:

1. It is indeed 2D. I've found that even just in 2D, it seems to be good enough. That said, I did adjust the simulation to account for the fact that if we just use standard inverse square law (which applies to 3D only - 2D would just be the "inverse law"), the sound's geometric attenuation still behaves properly. For afterglow, which I assume means "reverb tail", a bit of tweaking was required to find the exact coefficient necessary to make sure it behaves properly. For geometric attenuation, we raise the distance between adjacent rays to the 1.5'th power to calculate the attenuation.

2. The walls can indeed be adjusted like that. For each wall, you can adjust both the reflectivity (decided on this instead of absorption, since it's a bit more intuitive for unsophisticated users), and the diffusivity (otherwise known as scattering). The diffusivity is a tricky concept, because it doesn't really make any difference except in the case of impacts/impulses, like drums. In that case, a high diffusivity avoids any "fluttering", and simulates a very random/rough wall surface. In both cases, this is tunable as a function of frequency. So yes, you can achieve a real "morphing room mode" effect by giving different walls different properties. If you place the microphones to the right of a large room, the residual afterglow will sound like it's coming "from the left".

I'm hope you're glad I thought of this stuff!

Thanks for your response. I had also forgotten about this thread.

Although you have given thought to a lot of the behaviors, it appears to me that the quantitative apects could easily be inaccurate. But as long as it sounds good and/or is useful, I don't see a problem.

"Afterglow" and "reverb" are two different mechanisms. Reverb depends on the space as well as the boundary conditions. Afterglow depends on the space. If an effect occurs somewhere in (for example) unbounded 2-D space, the afterglow at a point distant from the source continues indefinitely, although diminishing with time. In 3-D unbounded space, there is no afterglow, i.e. no indication that anything has happened after (for example) the expanding "shell" from an impulsive point source has passed by points in the space. Although I assume your 2-D spaces are bounded, I cannot help but wonder if afterglow is incorporated during the calculations. If it's included, then to be accurate, it would need to be removed for accurately simulating 3-D.

As the author of the book below suggests: Imagine a 2-D radio that never seems to shut off, even though it was. He also writes, "In fact, 2D problems are often awkward...."

For most people, this is completely academic, but you invited questions. And you are solving an awkward problem, hoping that it represent 3-D accurately.

Reference:

Gabriel Barton. Elements of Green's Functions and Propagation: Potentials, Diffusion, and Waves. Oxford Science Publications, reprinted with corrections 1991, pages 278-282, 11.4 Wavefronts and afterglow.