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    Replay Gain

    Replay gain will automatically adjust the volume of the currently played song, relative to other songs, as determined by the person who encoded the audio file. To enable replay gain, see Settings menu.

    To handle this, Amarok relies on metadata embedded in the audio file:

    1. If no replay gain information is embedded, Amarok will not adjust the volume
    2. If replay gain information is found, it will be written into Amarok's database

    During playback, Amarok will only look into its own database for this information. Updates to the metadata of the file will not always get written into the database during a collection update (e.g. replay gain is deleted from file).

    This can lead to unexpected behavior: Songs from the same artist play at different volume levels etc.

    Is replay gain being used?

    To figure out if the volume problem is caused by replay gain or bad encoding:

    • Disable replay gain processing (see above)
    • Start Amarok in debug mode and search for gain- related output:
    amarok -d --nofork | grep gain

    If replay gain is active for the played song, the output will be

    Using gain of -10.28 with relative peak of -1

    View replay gain information

    For .flac files, "metaflac" can be used to view embedded replay gain data:

    metaflac --list Millencolin\ -\ Balanced\ Boy.flac

    Among other things, this will show something like this:

    METADATA block #2
     type: 4 (VORBIS_COMMENT)
     is last: false
     length: 390
     vendor string: reference libFLAC 1.2.1 20070917
     comments: 14
       comment[9]: REPLAYGAIN_REFERENCE_LOUDNESS=89.0 dB
       comment[10]: REPLAYGAIN_TRACK_GAIN=-1.55 dB
       comment[11]: REPLAYGAIN_TRACK_PEAK=0.75894165
       comment[12]: REPLAYGAIN_ALBUM_GAIN=-4.19 dB
       comment[13]: REPLAYGAIN_ALBUM_PEAK=0.98712158

    To view this tracks information within the Amarok database:

    select id, title, albumgain, albumpeakgain, trackgain, trackpeakgain from tracks where title like "Balanced%";

    Will show:

    | id    | title            | albumgain | albumpeakgain | trackgain | trackpeakgain |
    | 10459 | Balanced Boy     |      0.53 |      -5.60297 |      0.44 |      -5.60297 |

    Note the difference in loudness levels

    Delete replay gain information

    First, delete the metadata from the file:

    metaflac --remove-replay-gain Millencolin\ -\ Balanced\ Boy.flac

    After that, update your Amarok collection. If it is still using replay gain, update the database entry:

    update tracks set albumgain=-1,albumpeakgain=-1,trackgain=-1,trackpeakgain=-1 where id=10459

    Restart Amarok and the log output should now show the updated values being used.

    Feel free to try and mess with the values manually to improve volume levels.