Sound reflection

The word reflection is derived from the Latin reflectere (to reflect). The process should not be confused with diffraction and refraction. In general, reflection occurs when a wave (in acoustics, a sound wave) is reflected from a surface. If the propagation of the wave is represented by rays perpendicular to the wave front, these rays obey the law of reflection, i.e. the entrance angle of the incident ray is equal to the exit angle and the rays are in the same plane of incidence.

In room and building acoustics, the case of airborne sound waves falling on a surface is particularly interesting. If the impedance of the surface deviates from the impedance of air, the sound wave is more or less reflected.