Sound Pressure Level Calculator

Sound pressure level is represented by the symbol SPL, which is defined as the ratio of the effective value of the sound pressure to be measured p(e) to the reference sound pressure p(ref), taking the common logarithm and multiplying it by 20, that is:

SPL=20LOG(10)[p(e)/p(ref)]

The unit is decibel (dB).

The reference sound pressure p(ref) in air is generally taken as 2*10E-5 Pa, which is the sound pressure value that the normal human ear can just perceive the existence of 1 kHz sound, that is, the audible threshold sound pressure of 1 kHz sound. Generally speaking, below this sound pressure value, the human ear can no longer perceive the existence of this sound. Obviously, the sound pressure level of the audible threshold sound pressure is zero decibel.

Sound pressure level (SPL):

Sound pressure level (SPL):
SPL = 20log₁₀(P/P_ref)

SPL = Sound pressure level (SPL)

P = Effective sound pressure

P_ref = Reference sound pressure