loudnessnormalisointi

Loudness normalisointi, often referred to as loudness normalization or loudness matching, is a process used in audio production and distribution to ensure that the perceived loudness of different audio content is consistent. Instead of relying on peak levels, which can be misleading as they only measure the highest instantaneous sound pressure, loudness normalization focuses on the average loudness over a specific duration. This is crucial for preventing drastic and jarring volume changes when switching between different tracks, broadcasts, or streaming services.

The process typically involves measuring the integrated loudness of an audio program, which is a time-averaged measurement that better reflects how humans perceive loudness. Common measurement scales include LUFS (Loudness Units relative to Full Scale) or LKFS (Loudness, relative to Full Scale). Once the integrated loudness is determined, the audio is adjusted by either increasing or decreasing its gain to meet a target loudness level. For example, streaming services often set a target of -14 LUFS. If a track is measured at -10 LUFS, it will be turned down by 4 LUFS to match the target. Conversely, a track measured at -18 LUFS would be turned up by 4 LUFS.

This technique is widely adopted by broadcasters, streaming platforms like Spotify, Apple Music, and YouTube, and in mastering for various media. It greatly improves the listening experience by eliminating the need for listeners to constantly adjust their volume controls. Loudness normalization helps create a more equitable and enjoyable audio landscape, ensuring that all content, whether music, podcasts, or commercials, is presented at a comfortable and consistent volume.