Editing Acoustics (section)

== Definition ==
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Acoustics is defined by [[ANSI/ASA S1.1-2013]] as "(a) Science of [[sound]], including its production, transmission, and effects, including biological and psychological effects. (b) Those qualities of a room that, together, determine its character with respect to auditory effects."

The study of acoustics revolves around the generation, propagation and reception of mechanical waves and vibrations.

::'''[[File:Cause-effect diagram for acoustics.svg|The fundamental acoustical process]]'''

The steps shown in the above diagram can be found in any acoustical event or process. There are many kinds of cause, both natural and volitional. There are many kinds of transduction process that convert energy from some other form into sonic energy, producing a sound wave. There is one fundamental equation that describes sound wave propagation, the [[acoustic wave equation]], but the phenomena that emerge from it are varied and often complex. The wave carries energy throughout the propagating medium. Eventually this energy is transduced again into other forms, in ways that again may be natural and/or volitionally contrived. The final effect may be purely physical or it may reach far into the biological or volitional domains. The five basic steps are found equally well whether we are talking about an [[earthquake]], a submarine using sonar to locate its foe, or a band playing in a rock concert.

The central stage in the acoustical process is wave propagation. This falls within the domain of physical acoustics. In [[fluid]]s, sound propagates primarily as a [[Longitudinal wave|pressure wave]]. In solids, mechanical waves can take many forms including [[longitudinal waves]], [[transverse waves]] and [[surface waves]].

Acoustics looks first at the pressure levels and frequencies in the sound wave and how the wave interacts with the environment. This interaction can be described as either a [[diffraction]], [[Interference (wave propagation)|interference]] or a [[Reflection (physics)|reflection]] or a mix of the three. If several [[Transmission medium|media]] are present, a [[refraction]] can also occur. Transduction processes are also of special importance to acoustics.