Sound intensity level or acoustic intensity level is a logarithmic measure of the sound intensity in comparison to the reference level of 0 dB (decibels).

The measure of a ratio of two sound intensities is

$$

L_\mathrm{J}=10\, \log_{10}\left(\frac{J_1}{J_0}\right)\ \mathrm{dB}

where J₁ and J₀ are the intensities.

The sound intensity level is given the letter "L_J" and is measured in "dB". dB is dimensionless.

If J₀ is the standard reference sound intensity, where

$J\_0\; =\; 10^\{-12\}\; \backslash ,\; \backslash frac\{\backslash mathrm\{W\}\}\{\backslash mathrm\{m\}^2\}$

(W = watt), then instead of "dB" we use "dB SIL". (SIL = sound intensity level).

External links

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• Conversion: Sound intensity level to sound intensity

Acoustics | Physical quantity | Sound

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