Sound Pressure

Sound pressure or acoustic pressure is the local pressure deviation from the ambient (average, or equilibrium) atmospheric pressure caused by a sound wave. Sound pressure in air can be measured using a microphone, and in water using a hydrophone. The SI unit for sound pressure p is the pascal (symbol: Pa).

Sound pressure level (SPL) or sound level is a logarithmic measure of the effective sound pressure of a sound relative to a reference value. It is measured in decibels (dB) above a standard reference level. The commonly used "zero" reference sound pressure in air or other gases is 20 µPa RMS, which is usually considered the threshold of human hearing (at 1 kHz).

Read more about Sound PressureInstantaneous Sound Pressure, Sound Pressure Level

Other articles related to "sound pressure, sound, pressure, sounds":

Acoustic Source Localization - Overview
... Traditionally sound pressure is measured using microphones ... describing their sensitivity as function of the direction of the incident sound ... is independent of the direction of the incident sound ...
Acoustic Wave - Measurement
... Sound pressure can be measured directly using a microphone ... Sound intensity can be measured using different combinations Microphone and particle velocity probe (p-u probe) Two microphones (p-p probe) Two particle velocity probes ... The sound pressure level is given by where is the root-mean square pressure in Pa is the reference value of 2*10-5 Pa The particle velocity level is given by where is the root-mean square particle ...
Sound Frequency And Emotions - Limits of Perception
... The human ear can nominally hear sounds in the range 20 Hz (0.02 kHz) to 20,000 Hz (20 kHz) ... This effect of phase variance upon the resultant sound is known as beating ... The intensity range of audible sounds is enormous ...
Sound Pressure Level - Examples of Sound Pressure and Sound Pressure Levels
... Sound pressure in air Source of sound Sound pressure Sound pressure level Sound in air pascal RMS dB re 20 μPa Shockwave (distorted sound waves > 1 atm waveform valleys ...
Sound Energy Density
... The sound energy density or sound density (symbol E or w) is an adequate measure to describe the sound field at a given point as a sound energy value ... In opposite to the sound intensity I, which gives the sound power per area A, the sound energy density E (also sound density) describes the time medium value of ... The sound energy density E (or w) for an even-proceeding sound wave is , where I is the sound intensity in W/m2 and c is the sound speed in m/s ...

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