Diffusion

Diffusion, in acoustics, is the scattering of sound so that reflected energy spreads in many directions rather than bouncing back as a single strong reflection.^[1] In a diffuse field, reflections arrive evenly from around the listener, which is heard as a smooth and enveloping sense of space.

In sound design and virtual acoustics, controlling diffusion shapes how rough or smooth a reverberant space feels and helps avoid harsh, flat echoes. It is an important tool for making rooms sound natural, since real spaces almost always scatter sound to some degree.^[2]