Table of Contents

Monitoring the Signal Level

Within Wwise, the signal can be measured in different ways. One example is loudness level.

Loudness Overview

The ITU-R BS.1770 and EBU R128 standards provide recommendations and specifications for measuring the loudness level and loudness range of a given audio program in loudness units (LU or LUFS). It also provides specifications and recommendations for the True Peak level. Wwise implements these specifications and recommendations in the Loudness Meter view and Meter view.

Measurements

Wwise offers different measurements of the PCM signal:

Measurement

Description

Loudness level

Provides a measurement the perceptual loudness of a digital signal. The loudness level can be calculated using different time window sizes.

The Loudness level is available in the Loudness Meter view.

Units: LUFS or LU

Loudness range

Provides a statistical analysis of the loudness values over a period of time and a measure of the dynamic range.

The Loudness range is available in the Loudness Meter view.

Units: LU

True-Peak level

Provides an estimate of the maximum continuous signal level in the analogue world. This value is useful to ensure that the digital to analogue converter or an external codec is not saturated.

The True Peak level is available in the Meter View.

Units: dBTP

Peak level

Provides a measurement of the maximum or minimum values of a PCM signal for a very short period of time.

The peak level is shown at the following locations in Wwise:

  • Wwise Toolbar

  • Master-Mixer Console

  • Mixing Desk

  • Meter view

Units: dBFS

Root mean square (RMS)

The RMS level is measured with the peak meter values and does an average over a very short period of time.

The RMS level is available in the Meter View.

Units: dBFS

Loudness Units

The EBU R128 and ITU-R BS.1770 define units for measuring loudness. Loudness is not measured in dBFS.

Unit

Description

Loudness Unit (LU)

0 LU is equal to the reference level (by default -23 LUFS).

Note: The default value of 23 LUFS can be changed in the Loudness Meter settings.

Loudness Unit Full Scale (LUFS)

0 LUFS/LKFS is equal to 0 dBFs @ 1 kHz according to ITU-R BS.1770-3 and EBU R128

LKFS

LKFS is the same as LUFS.

ITU-R BS.1770-3 are using the terms LKFS.

EBU R128 and using LUFS.