ReplayGain on Mac: track gain vs album gain
If you mix albums from different eras, sooner or later one song comes in much louder than the last and you end up reaching for the volume. ReplayGain fixes that without modifying your files. This guide explains how it works, the difference between track gain and album gain, and which one suits you.
1. The problem it solves
Every album is mastered at a different level: a seventies record and a modern remaster can differ by several decibels. With a big library and shuffle, those jumps are obvious at every track change.
2. ReplayGain doesn’t touch the audio
ReplayGain measures the loudness of each file and stores the result as tags (for example REPLAYGAIN_TRACK_GAIN and REPLAYGAIN_ALBUM_GAIN, plus peak values). The player reads those tags and applies the gain during playback. The file stays exactly as it was, unlike destructive normalization, which rewrites the audio samples.
3. Track gain or album gain
- Album: applies the same correction to every song on a record. The loudness differences the artist intended between songs are kept. It’s the right choice when you listen to whole albums.
- Track: levels each song on its own. It’s best for mixed playlists and shuffle, where songs come from different albums.
4. Where the tags come from
A scanning program calculates them, not the player. There are free options, such as loudgain on the command line. Always scan by complete album so track and album gain are written together. Back up the folder before writing tags in bulk. Sonora reads the tags your files already carry, and the library has a “No ReplayGain” filter that shows which albums have no loudness information.
5. Turn it on in Sonora
Go to Settings ▸ Playback ▸ ReplayGain and choose By album, By track or Off. Below it you’ll find the ReplayGain preamp, to raise or lower the reference level. ReplayGain isn’t applied over AirPlay.
6. ReplayGain and bit-perfect
Applying gain changes the samples that reach the DAC, so with ReplayGain on playback is no longer bit-perfect. If purity is your priority, leave it Off and set the volume by hand. The details are in our bit-perfect guide.
Common problems
- I don’t hear any change: your files have no tags. Check the “No ReplayGain” filter.
- A song distorts or clips: the gain is raising a track with high peaks too much. Lower the preamp.
- Albums still sound different from each other with “By album”: that’s expected; this mode keeps the relative level within each album. To level everything, use “By track”.
Try it with your library
Sonora is a native macOS player (Apple silicon, macOS 14 or later). Try it free for 14 days with every feature, no card and no sign-up.