4. Acoustic diffusion

The diffusion of sound is a consequence of the multiple reflections and diffractions that it suffers on irregular surfaces or obstacles to propagation. The diffusers are used to achieve a homogeneous sound field by scattering the reflected acoustic energy in all directions. When a diffuse field is achieved, the acoustic energy is homogeneously and isotropic distributed both in space and in time.

The diffusers allow to correct the early and late reflections and the normal modes of a room.

Unlike the systems of isolation and absorption, in which the most important are the characteristics of the material, the diffusers can be built in any material provided a proper surface design. When a good spatial distribution is achieved, a good temporary dispersion is usually achieved as well.

The design of the surface irregularities can be computed according to different numerical sequences with basis on the main principles of acoustic wave interferences [11].
