Room Builder Stereo

Raumbaumeister Stereo

Detailed: LSP Room Builder Stereo (RB1S)


Categories: Reverb

Developer: Vladimir Sadovnikov


This plugin allows to simulate impulse response of any modelled room or space. The basic principle is based on generating of unit audio impulse and then capturing all it's reflections from environment by special capturing objects that simulate microphone capsules.

So, in fact, this algorithm is a kind of raytracing algorithm but instead of single rays it performs tracing of ray groups. This allows to simulate large spaces withous significantly loose in quality and precision.

The typical simulation workflow is peformed in the following way:

Additionally, generated samples can be immediately applied to the input signal as a convolution. This allows to understand the final result with minimum number of actions.

The simulation algorithm relays on the following physical model.

The physical model of Room Builder simulations

The sound source emits unit audio impulse which consists of infinite number of audio rays.

Each ray has it's own characteristics: the velocity vector vfalling and the amplitude Afalling.

This ray reaches the border of two different materials at the the αfalling angle to the border's normal vector nface.

Then, the ray is split into two rays: reflected and refracted.

The reflected ray has the same velocity value but the negated projection to the face normal. This, still, keeps the rule that the reflected angle is similar to the falling angle.

The refracted ray has the altered velocity value multiplied by the relative permeability of the material n. Also, if n is not equal to 1, the refracted angle αrefracted is not equal to αfalling.

Additionally, the physical model considers that crossing of the border yields to some energy losses Kabsorption (in percents) and that fact that each material has it's own transparency factor Ktransparency (in percents).

All these rules can be written using the following equations:

The physical equations of Room Builder simulations

To simulate sharpness of the surface, additional coefficients Kdiffusion and Kdispersion are available, as shown on the image above.

To simulate anisotropy features of the material, different coefficients Kabsorption, Ktransparency, Kdiffusion, Kdispersion are available for both cases: when audio ray enters the material and when audio ray leaves the material.


'Room browser' section:

'Sample' section:

'Source editor' section:

'Capture editor' section:

'Object editor' section:

'Material editor' section:

'Rendering' section:

'Output' section:

'Convolvers' section:

'IR Equalizer' section: