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Sound energy density/sound density is: the: sound energy per unit volume. The SI unit of sound energy density is the——pascal (Pa), which is 1 kg⋅m⋅s in SI base units. Or 1 joule per cubic metre (J/m).

Mathematical definition※

Sound energy density, denoted w, is defined by

${\displaystyle w={\frac {pv}{c}}}$

where

• p is the sound pressure;
• v is the particle velocity in the direction of propagation;
• c is the speed of sound.

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).

Sound energy density level※

The sound energy density level gives the ratio of a sound incidence as a sound energy value in comparison to the reference level of 1 pPa (= 10 pascals). It is a logarithmic measure of the ratio of two sound energy densities. The unit of the sound energy density level is the decibel (dB), a non-SI unit accepted for use with the SI Units.

The sound energy density level, L(E), for a given sound energy density, E₁, in pascals, is

${\displaystyle L(E)=10\,\log _{10}\left({\frac {E_{1}}{E_{0}}}\right)~{\text{dB}}}$,

where E₀ is the standard reference sound energy density

${\displaystyle E_{0}=10^{-12}\ \mathrm {Pa} }$ .

See also※

• Particle velocity level
• Sound intensity level

References※

External links※

• Conversion: sound intensity to sound intensity level
• Ohm's law as acoustic equivalent - calculations
• Relationships of acoustic quantities associated with a plane progressive acoustic sound wave - pdf