Characteristic Symbols Particle velocity v, SVL Sound intensity I, SIL | Sound pressure p, SPL Particle displacement δ Sound power P, SWL | |
Sound energy density or sound density is the sound energy per unit volume. The SI unit of sound energy density is the pascal (Pa), that is the joule per cubic metre (J/m3) in SI based units.
Mathematical definition
Sound energy density, denoted w, is defined by
where
The terms instantaneous energy density, maximum energy density, and peak energy density have meanings analogous to the related terms used for sound pressure. In speaking of average energy density, it is necessary to distinguish between the space average (at a given instant) and the time average (at a given point).
References
Sound energy density Wikipedia(Text) CC BY-SA