A Weighting

A standard weighting of the audible frequencies designed to reflect the response of the human ear to noise.

Acoustic Calibrator

An instrument that provides a reference noise source that is used to calibrate and check the performance of a Sound Level Meter.

C Weighting

A standard weighting of the audible frequencies used for the measurement of Peak Sound Pressure level.  This weighting is based on a relatively flat response and is used for recording AC outputs from the sound level meter.

Data Logging

Measurements can be stored in the Sound Level Meter for download to a PC

dB(A)

Decibels A weighted

dB(C)

Decibels C Weighted

Decibel (dB)

The units of sound level and noise exposure measurement

% Dose

The noise exposure expressed as a percentage (%) of a fixed level for 8 hours

F Weighting

A standard weighting that gives a flat response over a wider range of frequencies than the C-Weighting.  Primarily used for frequency analysis or an objects sound

Fast Time Weighting

A standard time weighting applied by the Sound Level Meter

IEC 60804:1984

The International Standard for Integrating & Integrating-Averaging Sound Level Meters

IEC 61672:1999

The International standard for Sound Level Meter and Integrating Averaging Sound Level Meters that will replace both IEC 60651 and IEC 60804

IEC 60651:1979

The International Standard for Sound Level Meters

Impulse Time Weighting

A standard time weighting applied by the Sound Level Meter

Integrating Averaging
Sound Level Meter

A Sound Level Meter which accumulates the total sound energy over a measurement period and calculates an average

L_A10

The noise level exceeded for 10% of the measurement period with 'A' frequency weighting calculated by statistical analysis

L_A90

The noise level exceeded for 90% of the measurement period with 'A' frequency weighting calculated by statistical analysis

L_AE

Sound Exposure Level (SEL) with 'A' frequency weighting

L_Aeq,t

Equivalent continuous sound pressure level. A measure of the average sound pressure level during a period of time, t, in dB with 'A' weighting.

L_AF

Sound level with 'A' Frequency weighting and Fast Time weighting

L_AFmax

The maximum Sound level with 'A' Frequency weighting and Fast Time weighting

L_AFTeq

Takt maximal sound level as defined by DIN 45641

L_AI

Sound level with 'A' Frequency weighting and Impulse Time weighting

L_AImax

The maximum Sound level with 'A' Frequency weighting and Impulse Time weighting

L_AS

Sound level with 'A' Frequency weighting and Slow Time weighting

L_ASmax

The maximum Sound level with 'A' Frequency weighting and Slow Time weighting

L_CE

Sound Exposure Level (SEL) with 'C' frequency weighting

L_ceq,t

Equivalent continuous sound pressure level. A measure of the average sound pressure level during a period of time, t, in dB with 'C' weighting.

L_CF

Sound level with 'C' Frequency weighting and Fast Time weighting

L_CFmax

The maximum Sound level with 'C' Frequency weighting and Fast Time weighting

L_CI

Sound level with 'C' Frequency weighting and Impulse Time weighting

L_CImax

The maximum Sound level with 'C' Frequency weighting and Impulse Time weighting

L_Cpeak

Peak Sound pressure level with 'C' frequency weighting

L_CS

Sound level with 'C' Frequency weighting and Slow Time weighting

L_CSmax

The maximum Sound level with 'C' Frequency weighting and Slow Time weighting

L_EP,d

Daily personal noise exposure

L_eq

Equivalent continuous sound pressure level. A measure of the average sound pressure level during a period of time, t, in dB

L_IeqT

Impulse weighted L_eq,t as defined by DIN 45641

_n

Statistical analysis of noise levels. The n denotes the percentage exceedence.

L_ZE

Sound Exposure Level (SEL) with 'Z' frequency weighting

L_Zeq,t

Equivalent continuous sound pressure level. A measure of the average sound pressure level during a period of time, t, in dB with 'Z' weighting.

L_ZF

Sound level with 'Z' Frequency weighting and Fast Time weighting

L_ZFmax

The maximum Sound level with 'Z' Frequency weighting and Fast Time weighting

L_ZI

Sound level with 'Z' Frequency weighting and Impulse Time weighting

L_ZImax

The maximum Sound level with 'Z' Frequency weighting and Impulse Time weighting

L_ZS

Sound level with 'Z' Frequency weighting and Slow Time weighting

L_ZSmax

The maximum Sound level with 'Z' Frequency weighting and Slow Time weighting

Overload

The input to the Sound Level Meter is too high for the current measurement range. Change the range

Peak

The maximum value reached by the sound pressure at any instant during a measurement period (in dB usually with C frequency weighting)

SEL

Sound Exposure Level, displayed as L_AE, L_CE or L_ZE

Slow Time Weighting

A standard time weighting applied by the Sound Level Meter

Sound Level

Sound Pressure Level with a Frequency weighting, such as dB(A)

Sound Level Meter

An instrument for measuring various noise parameters

SPL

Sound Pressure Level, the basic measure of noise loudness, expressed in decibels

Statistical Analysis

A calculation performed by a Sound Level Meter on the noise levels measured during the measurement period to describe the statistical spread of the noise.

Type 2

General Field Grade for Sound Level Meter

Type 1

Laboratory & Field Grade for Sound Level Meters

Under Range

The input to the Sound Level Meter is too low for the current measurement range. Change the range

Z Weighting

Z weighting is a flat frequency response between 10Hz and 20kHz ±1.5dB excluding microphone response.