Simple Explanation

In acoustics, diffusion is the scattering of sound to reduce echoes and make a space sound more natural. A diffuser is a panel or surface that spreads out sound waves.

Concise Technical Definition

Diffusion refers to the scattering of sound energy in many directions to avoid hard reflections while preserving the room’s natural liveliness. It is achieved using acoustic diffusers—often mathematically designed, but can also occur naturally (e.g., bookshelves).

Layman-Friendly Analogy

Like how light scatters off a disco ball instead of bouncing in one direction, a diffuser breaks up sound reflections so the room feels open but not echoey.

Industry Usage Summary

In studios, theaters, and listening rooms, diffusion is used to reduce flutter echoes and comb filtering without deadening the space. Engineers use diffuser panels (e.g., QRD or skyline types) to scatter sound evenly across a range of frequencies. Even irregular furniture can act as natural diffusers.

Engineering Shortcut

Widely spread out or scattered; not concentrated.

Full Technical Explanation

Diffusion in acoustics refers to the process of scattering sound energy across a broad spatial area to reduce harsh reflections and standing waves. Unlike absorption, which removes sound energy, diffusion maintains sound energy in the room while redistributing it. Diffusers—whether manufactured using quadratic residue or skyline patterns, or formed naturally (e.g., uneven surfaces)—are used to preserve clarity and spaciousness in critical listening environments. Effective diffusion depends on frequency, surface geometry, and room placement.