This is a work to rule, based on ITU-R BS.1770-3. To characterise an audio signal the measures of Programme Loudness, Loudness Range and Maximum True Peak Level are used.
The Program Loudness Level is normalized to -23LUFS [Loudness Units referenced to Full Scale] with a permitted deviation of +/- 1LU. The measurement includes a gating method as specified in ITU-R BS.1770 (summarized in EBU Tech Doc 3341).
Loudness Range LRA measures the variation of loudness on a macroscopic timescale. It is supplementary to the measure of overall (integrated) loudness. Units are LU. The algorithm for calculating it can be found in EBU Tech Doc 3342.
The Maximum Permitted True Peak Level of a program during production is -1dBTP, measured with a meter compliant with both ITU-R BS.1770 and EBU Tech Doc 3341.
- EBU-web-page (external link)