Spotify loudness normalization
Spotify loudness normalization is a feature that aims to provide a consistent listening experience across different tracks, regardless of their original loudness. When a user plays a song on Spotify, the streaming service applies loudness normalization to the track to ensure that it plays at a consistent volume level relative to other tracks in the playlist or album.
The goal of loudness normalization is to prevent songs with higher overall loudness levels from sounding overly loud and overpowering songs with lower loudness levels. Spotify uses the ReplayGain algorithm to analyze the loudness of each track and adjust its playback level accordingly. The algorithm analyzes the track's loudness level, calculates the difference between the track's loudness level and the reference loudness level, and applies gain adjustment to bring the track's loudness level to the reference level.
Spotify's loudness normalization feature is enabled by default, and users can choose to turn it off in the settings if they prefer to listen to tracks at their original loudness levels.