Why is the reference pressure for dB SPL 20uPa?

1. What is the reference level for dB SPL?
2. How do you calculate dB SPL?
3. What does 0 dB SPL mean?

What is the reference level for dB SPL?

Sound pressure level (SPL) is the pressure level of a sound, measured in decibels (dB). It is equal to 20 x the Log¹⁰ of the ratio of the Root Mean Square (RMS) of sound pressure to the reference of sound pressure (the reference sound pressure in air is 2 x 10-5 N/m2, or 0,00002 Pa).

How do you calculate dB SPL?

The sound pressure level (SPL) is defined asSPL=20 log10(PP0)dB(re. 2×10−6Pa)Likewise, sound intensity level (SIL) and sound power level (PWL) are normally expressed in decibels.

What does 0 dB SPL mean?

The decibel of sound pressure level (dB SPL) takes as a reference the minimum sound pressure level that the average human ear can detect. The smallest audible sound to humans is typically 0 dB SPL (hearing threshold).