Loudness normalization

Audio gets delivered to us at different volume levels.

We use loudness normalization to balance soft and loud songs, creating a more balanced uniform experience.

Note: The web player and 3rd-party devices (e.g. speakers and TVs) don’t use loudness normalization.

How we adjust loudness

We adjust tracks to -14 dB LUFS, according to the ITU 1770 (International Telecommunication Union) standard.

We normalize an entire album at the same time, so gain compensation doesn’t change between tracks. This means the softer tracks are as soft as you intend them to be.
We adjust individual tracks when shuffling an album or listening to tracks from multiple albums (e.g. listening to a playlist).

Positive or negative gain compensation gets applied to a track while it’s playing.

Negative gain is applied to louder masters so the loudness level is -14 dB LUFS. This lowers the volume in comparison to the master - no additional distortion occurs.
Positive gain is applied to softer masters so the loudness level is -14 dB LUFS. We consider the headroom of the track, and leave 1 dB headroom for lossy encodings to preserve audio quality.
Example: If a track loudness level is -20 dB LUFS, and its True Peak maximum is -5 dB FS, we only lift the track up to -16 dB LUFS.

Premium listeners can also choose volume normalization levels in the app settings to compensate for a noisy or quiet environment

Loud: -11dB LUFS
Note: We set this level regardless of maximum True Peak. We apply a limiter to prevent distortion and clipping in soft dynamic tracks. The limiter’s set to engage at -1 dB (sample values), with a 5 ms attack time and a 100 ms decay time.
Normal: -14dB LUFS
Quiet: -19dB LUFS

Loudness normalization means we don’t always play your track at the level it’s mastered.

Target the loudness level of your master at -14dB integrated LUFS and keep it below -1dB TP (True Peak) max. This is best for lossy formats (Ogg/Vorbis and AAC) and makes sure no extra distortion’s introduced in the transcoding process.
If your master’s louder than -14dB integrated LUFS, make sure it stays below -2dB TP (True Peak) to avoid extra distortion. This is because louder tracks are more susceptible to extra distortion in the transcoding process.