Lautheitsnormen

Lautheitsnormen are standards and guidelines for measuring and regulating the perceived loudness of audio content. They aim to deliver a consistent listening experience across programs, channels and devices by normalizing loudness rather than relying solely on peak levels. This helps reduce sudden jumps in volume between programs, commercials and ads.

The core concept is loudness, usually expressed in LUFS (Loudness Units relative to Full Scale) or LKFS in some regions. Measurements distinguish integrated loudness (over an entire program) from short-term or momentary values. In addition, parameters such as Loudness Range (LRA) describe how much the loudness varies within a piece of content. Standards most commonly rely on algorithms defined in the ITU-R BS.1770 family, which provide a consistent way to compute loudness across devices and formats.

Prominent standards include the European Broadcasting Union’s EBU R128, which specifies target integrated loudness and peak limits and is widely adopted in European broadcasting. In the United States, standards associated with the CALM Act and ATSC A/85 influence loudness targets for U.S. broadcasts. ITU-R BS.1770 serves as the common computational basis for these and many other national or platform-specific rules. The effects of these standards extend to production, mastering, streaming and broadcast distribution, where tools implement automatic loudness normalization to meet platform requirements.

Implementation typically involves loudness metering during production and mastering, followed by adjustment of gain or dynamics to reach target levels. While effective, challenges remain, including content with mixed speech and music, and the balance between loudness normalization and preserving dynamic range. Ongoing development seeks to refine algorithms and adaptation for multi-channel and immersive formats.