Editing Acoustical engineering (section)

==Fundamental science==

Although the way in which sound interacts with its surroundings is often extremely complex, there are a few ideal sound wave behaviours that are fundamental to understanding acoustical design.  Complex sound wave behaviors include [[Absorption (acoustics)|absorption]], [[reverberation]], [[diffraction]], and [[refraction]]. Absorption is the loss of energy that occurs when a sound wave reflects off of a surface, and refers to both the sound energy transmitted through and dissipated by the surface material.<ref>Barron, 2002, ch. 7.1.</ref> Reverberation is the persistence of sound caused by repeated boundary reflections after the source of the sound stops. This principle is particularly important in enclosed spaces. Diffraction is the bending of sound waves around surfaces in the path of the wave. Refraction is the bending of sound waves caused by changes in the medium through which the wave is passing. For example, temperature gradients can cause sound wave refraction.<ref>Hemond, 1983, pp. 24–44.</ref> Acoustical engineers apply these fundamental concepts, along with mathematical analysis, to control sound for a variety of applications.