# Sound power

Sound power

Sound measurements

Sound power or acoustic power "P"ac is a measure of sonic energy "E" per time "t" unit.

It is measured in watts, or sound intensity "I" times area "A"::$P_\left\{mathrm\left\{acoustic = I cdot A$

The measure of a ratio of two sound powers is:$L_mathrm\left\{w\right\}=10, log_\left\{10\right\}left\left(frac\left\{P_1\right\}\left\{P_0\right\} ight\right) mathrm\left\{dB\right\}$

where:"P"1, "P"0 are the sound powers.

The sound power level PWL, LW, or LPac of a source is expressed in decibels (dB) and is equal to 10 times the logarithm to the base 10 of the ratio of the sound power of the source to a reference sound power. It is thus a logarithmic measure.

The reference sound power in air is normally taken to be 10−12 watt = 0 dB SWL.

Sound power is neither room dependent nor distance dependent. Sound power belongs strictly to the sound source.

Table: Sound power and sound power level of some sound sources

:

Usable music sound (trumpet) and noise sound (excavator) both have the same sound power of 0.3 watts, but will be judged psychoacoustically to be different levels.

ound power with plain sound waves

Between sound power and other important acoustic values there is the following relationship:

$P_\left\{ak\right\} = xi^2 cdot omega^2 cdot Z cdot A = v^2 cdot Z cdot A = frac\left\{a^2 cdot Z cdot A\right\}\left\{omega^2\right\} = frac\left\{p^2 cdot A\right\}\left\{Z\right\} = E cdot c cdot A = I cdot A$

where:

* [http://www.sengpielaudio.com/calculator-ak-ohm.htm Ohm's law as acoustic equivalent — calculations]
* [http://www.sengpielaudio.com/RelationshipsOfAcousticQuantities.pdf Relationships of acoustic quantities associated with a plane progressive acoustic sound wave — pdf]

Wikimedia Foundation. 2010.

### Look at other dictionaries:

• sound power — garso galia statusas T sritis Standartizacija ir metrologija apibrėžtis Garso bangų energija, per vienetinį laiko tarpą pereinanti per visą bangų fronto paviršių. atitikmenys: angl. acoustic power; sound power vok. akustische Leistung, f;… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

• sound power — garso galia statusas T sritis Standartizacija ir metrologija apibrėžtis Išspinduliuotų, perduodamų arba priimamų garso bangų galia. atitikmenys: angl. acoustic power; sound power vok. akustische Leistung, f; Leistung der Schallquelle, f;… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

• sound power — garso galia statusas T sritis fizika atitikmenys: angl. sound power vok. Schalleistung, f rus. мощность звука, f pranc. puissance acoustique, f; puissance du son, f …   Fizikos terminų žodynas

• sound power — garso galia statusas T sritis ekologija ir aplinkotyra apibrėžtis Garso bangų energija, per laiko vienetą praeinanti per visą bangų fronto paviršių. atitikmenys: angl. sound power vok. Schallkraft, f rus. звуковая волна, f; сила звука, f …   Ekologijos terminų aiškinamasis žodynas

• Sound power level — or acoustic power level is a logarithmic measure of the sound power in comparison to a specified reference level.The sound power level of a signal with sound power W is [ [http://hep.physics.indiana.edu/ rickv/Sound intensity.html Sound Power,… …   Wikipedia

• sound power level — garso galios lygis statusas T sritis Standartizacija ir metrologija apibrėžtis Apibrėžtį žr. priede. priedas( ai) Grafinis formatas atitikmenys: angl. sound power level vok. Schallstärkepegel, m rus. уровень интенсивности звука, m pranc. niveau… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

• sound power level — garso galios lygis statusas T sritis fizika atitikmenys: angl. sound power level vok. Schallstärkepegel, m rus. уровень звуковой мощности, m pranc. niveau de puissance sonore, m …   Fizikos terminų žodynas

• Power chord — Component intervals from root perfect fifth root …   Wikipedia

• Sound pressure — Sound measurements Sound pressure p, SPL Particle velocity v, SVL Particle displacement ξ Sound intensity I, SIL Sound power Pac Sound power level SWL Sound energy Sound energy d …   Wikipedia

• Power FM — Infobox Radio station name = 103.2 Power FM area = South Hampshire airdate = 4 December 1988 frequency = 103.2 MHz FM share = 7.0% share as of = September 2007 share source = [http://www.rajar.co.uk/listening/quarterly listening.php] format = CHR …   Wikipedia