Being a mastering engineer involves preparing my clients' music for digital distribution.
Nowadays, anyone involved in the production process must understand how digital platforms (Spotify, Apple Music, Tidal, Amazon, etc.) treat your music when broadcasting.
In the last few years, it has been introduced a new system of loudness normalization based on what is called LUFS. But what is LUFS? How does the LUFS normalization work? Moreover, how do each of the different streaming platforms normalize our music? What else shall we have to consider?
Let's start answering some common questions and clarify some basic concepts.
WHAT IS LUFS?
LUFS stands for Loudness Units relative to Full Scale. It has been introduced primarily by the broadcasting industry to level and normalize the perceived loudness of different shows and adverts over time. The music industry followed up, and now many streaming services (such as Spotify, Apple Music, YouTube, etc.) use this method to make the perceived loudness consistent during playback.
The peculiarity of LUFS is that it reacts not only on the average level of a song (like the RMS) but also takes into account how humans perceive different ranges of frequency, becoming, therefore, a more accurate scale to measure loudness, or better, perceived loudness.
Note: In this article, I refer to different metering systems such as dB FS or TP. If you are not confident with these scales, please read the article DB AND METERS...HOW ARE THOSE STRANGERS?
WHAT IS LOUDNESS NORMALISATION?
Loudness normalization is a process according to which a streaming platform turns the volume of a song up or down according to its LUFS reference. In other words, it doesn't matter if you are listening to a very dynamic Jazz song or a super compressed Metal one. They will playback at the same volume.
As you can see from the image above the two songs, after the normalization, sound at the same volume (perceived loudness). This will prevent the final listener to reach the volume control and readjust the volume every time a new song plays.
STANDING OUT: MASTERING FOR STREAMING PLATFORMS
Spotify and all the most common streaming platforms broadcast music at around -14 LUFS.
If a song sounds louder (for instance at -5 LUFS) the streaming platform will decrease the volume to -14 LUFS.
Comparing the two waveforms above, after normalization, is quite noticeable how the second master (red), sounds at the same volume as the first master (green).
The latter master (green), has been produced preserving dynamic, depth, transients, punch, and details resulting in a much more pleasant listening experience on streaming platforms.
WHAT HAPPENS IF A MASTER IS QUIETER THAN -14 LUFS?
Well, some streaming platforms leave those tracks as they are, and some others (for instance Amazon Music) will turn up the volume until it reaches its LUFS target.
This scenario can be dangerous for our tracks as peaks might hit a limiter used by streaming services altering the master and sometimes causing audible distortion.
At Master Your Tracks we produce masters for digital platforms which are loudness competitive, but at the same time respectful of the dynamic range ensuring the best translation between multiple platforms (Spotify, Apple Music, TIDAL, Sound Could, etc.)
TRUE PEAKS
Another aspect to consider when mastering dor digital platforms is true peaks.
Most digital platforms (Spotify, Apple Music, etc.) broadcast music in lossy format (Ogg Vobis, AAC).
It is the platform itself that converts the master from a lossless to a lossy format. This process usually adds some gain. The louder the master the more the gain produced by the conversion.
It is understandable that, if we don't check accurately our true peaks, making sure they are below 0 dB FS the conversion process might cause some distortions.
Most of the digital platforms recommend producing masters with true peaks between -1 and -2 dB FS.
To get your music on iTunes and Apple Music badged and marketed as Apple Digital Master, your mastering engineer must be on the
Apple Digital Masters Provider List.
Master Your Track is on the
Apple Digital Masters Provider List.
Read More: WHAT IS APPLE DIGITAL MASTER?
STREAMING PLATFORMS
NORMALISATION AND TRUE PEAKS TABLE
Following there is a table that summarises normalization levels and recommended true peaks for the most common digital platform.
MEDIA | NORMALISATION (LUFS) | TRUE PEAKS | FORMAT |
Spotify | -14 LUFS | -1 dB TP | Ogg Vorbis |
Spotify Loud | -11 LUFS | -2 dB TP | Ogg Vorbis |
Apple Music | -16 LUFS | -1 dB TP | AAC |
Apple Podcast | -16 LUFS | -1 dB TP | AAC |
Tidal | -14 LUFS | -1 dB TP | AAC - FLAC |
Youtube | -14 LUFS | -2 dB TP | AAC |
Amazon Music | -13 LUFS | -2 dB TP | MP3 |
Deezer | -15 LUFS | -1 dB TP | FLAC |
Sound Cloud | -14 LUFS | -1 dB TP | Ogg Vorbis - AAC |
Pandora | -14 LUFS | -1 dB TP | AAC |
BandCamp | No Normalisation | -2 dB TP | MP3 |
FORMATS
The most common lossy streaming formats are:
Ogg Vorbis
AAC (Advanced Audio Codec) made by Apple
MP3 at different Kbps
The most common lossless streaming formats are:
FLAC
WAV