ReplayGain
More info
- Creator
- David Robinson
- Released
- 2001
- Type
- Metadata standard
A way of evening out perceived loudness between tracks by storing a volume adjustment in the file's tags instead of altering the audio.
The player reads a number in decibels and turns the volume up or down at playback, leaving the file untouched. There are two values: track gain for shuffled playlists, and album gain, which preserves deliberate level differences between songs on a record. A stored peak value lets the player avoid boosting so far that it clips.
The proposal arrived in 2001, deep into the loudness war that made every other track in a mixed collection too hot. It became standard in the FLAC and Vorbis world long before streaming services started normalising. Version 2.0 swapped its home-grown measurement for LUFS per EBU R 128.