Acoustics Glossary
Welcome to AcSoft's Acoustics Glossary!
Whether you are new to acoustics or need a quick refresher, our bite sized videos break down complex acoustic terms into simple, easy to understand explanations.
We will cover all the essential terms you will encounter in environmental noise, building acoustics and beyond!
Have a question or want us to cover a specific acoustics term, contact us!
A-Z of Acoustic Terms
Dynamic Range
Dynamic range is the span between the quietest and loudest sounds a microphone or sound level meter can measure accurately.
Frequency Range
Frequency range is the span of frequencies a microphone, loudspeaker, or system can handle reliably. It’s usually defined between two cutoff points, where the output drops by 3 decibels compared to the flat response.
LEQ
LEQ, or Equivalent Continuous Sound Level, is one of the most important metrics in noise measurement and represents the average sound level over a set period.
LMAX
LMAX, or Maximum Sound Level, is the highest averaged sound pressure level recorded during a measurement period, based on a selected time weighting (like Fast or Slow).
LMIN
LMIN, or Minimum Sound Level, is the lowest sound pressure level recorded during a measurement period.
LPEAK
LPeak (Peak Sound Level) is the maximum instantaneous sound pressure level recorded during a measurement,
Noise Weighting
Noise weighting is all about how we measure sound in a way that reflects how humans actually hear it.
Particle Velocity
Particle velocity describes the back-and-forth motion of air particles when a sound wave passes through.
Pascals vs Decibels
We explain how Pascals relate to decibels, why the conversion is needed, and how the dB scale makes it easier to compare sounds across environments.
Peak Particle Velocity
PPV, or Peak Particle Velocity, is one of the most commonly used measurements in vibration monitoring. It describes the maximum speed at which particles in the ground or a structure move during a vibration event.
Polarisation in Microphones
Polarisation is the electrical charge applied to a microphone’s diaphragm to make it sensitive to sound.
Reverberation Time
Reverberation Time — commonly referred to as RT60 — is the time it takes for sound to decay by 60 decibels after a sound source stops.
Sound Pressure Level
Sound Pressure Level (SPL) is a way of expressing sound in decibels, based on the pressure variations a sound wave creates in the air.
VC Curves
VC Curves, or Vibration Criterion Curves, are used to define acceptable vibration levels for sensitive buildings, equipment, and spaces.
Knowledge Hub
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