Loudness-Normalisation - The practice of matching the perceived loudness of different material to a given target loudness value. To accommodate varying peak levels, the medium requires an approporiate headroom margin. Loudness-normalisation is now the default form for HDTV broadcasts, as well as most audio streaming services, although the target loudness level currently varies between different platforms. Loudness-normalisation is measured using the LUFS or LKFS scale. (