Reflected acoustic wave

Reflected Sound Wave

Professional Definition

A reflected sound wave is a wave that occurs as a result of interaction with the boundary of two media with different acoustic impedances (wave resistance).

This phenomenon occurs in accordance with the principle that the angle of incidence of the wave is equal to the angle of reflection (provided that the surface is flat and smooth relative to the wavelength). The reflected wave carries only a part of the energy of the original wave – the remaining energy is absorbed by the obstacle material or passes through to its other side (transmission). The summation of incident and reflected waves in an enclosed space leads to interference phenomena, the creation of a reverberation field, and the room's own modes (standing waves).

Acoustics in Simple Words

Imagine a game of pool. When the white ball (sound wave) hits the edge of the table (wall), it does not stop but bounces back and speeds in the opposite direction.

• If the edge is hard, the ball bounces strongly and almost does not lose speed (the equivalent of a concrete wall).

• If the edge were made of soft sponge, the ball would lose energy and bounce very weakly (the equivalent of acoustic panels or curtains).

In an empty room, sound behaves like thousands of rubber balls thrown simultaneously at the walls – they bounce repeatedly, creating a sound chaos that we call reverberation. The reflected wave is simply that “ball” which returns to your ear after colliding with an obstacle.

Summary

• Change of direction: A reflected wave is the sound that “turned back” or changed its flight path after hitting an obstacle.

• Acoustic effects: This phenomenon is directly responsible for the formation of echoes and reverberation in rooms.

• Interior adaptation: Control of reflected waves – through absorption (soft materials) or diffusion (diffusers) – is the foundation of designing professional recording studios and concert halls.