sound intensity level

in psychophysics, the average sound energy passing through a unit area per unit time perpendicular to the direction of sound wave propagation is called sound intensity. sound intensity is expressed by i, and the unit is watt/square meter. psychophysical research shows that people's perception of sound intensity is not directly proportional to the sound intensity, but proportional to its logarithm. this is why people use sound intensity levels to express sound intensity.

its unit is bell sound intensity level (bel, bel)

Ｌ＝ｌｏｇ （１０）［Ｉ／Ｉ０］＝ｌｇ（Ｉ/Ｉ０）

most people can distinguish two sounds with an intensity difference of one-tenth of a bell, so it is more convenient to use one-tenth of a bell as the unit of sound intensity. this unit is called decibel, or decibel for short. db), that is

ＳＩＬ＝１０ｌｏｇ（１０）［Ｉ／Ｉ０］＝１０ｌｇ（Ｉ／Ｉ０）

in the formula, i is the sound intensity, and i0=10^-12 watts/square meter is called the reference sound intensity. the common unit of sound intensity level is decibel (db).

sound intensity level:

sound intensity level calculation: sil =10log₁₀(I/I₀)

il = sound intensity level

i = sound intensity

I₀ = reference sound intensity