How to Master a Song: Loudness, Chain and Streaming

Learning how to master a song is a different skill from learning to mix one. Mixing decides what is in the record. Mastering takes that finished mix as a single stereo file and prepares it for the outside world, which means making it translate on speakers you have never heard and giving it a level that holds up next to whatever played before it.

Mastering versus mixing: what each one can fix

A mix problem stays a mix problem. If the kick and the bass fight for the same space, a limiter only makes the fight louder. Mastering works on the whole file at once, so it can balance the overall tone, control peaks and make a dull mix feel present, but it cannot separate two sounds that occupy the same frequencies.

If you can point at one element and say what is wrong with it, that is a mixing job. If the summary is that the track sounds small or uneven next to commercial records, that is what mastering is for.

The mastering chain, in order

There is no magic plugin order, but there is a logic: fix the tone first, control the dynamics, then raise the level.

• Corrective EQ, removing a resonance or a build up of low mids before anything else amplifies it.
• Compression, gluing the sections together so quiet parts do not fall away. Two or three decibels of gain reduction is plenty.
• Saturation, adding harmonics so the low end stays audible on phone speakers.
• Stereo work, widening what can be widened while the kick and the bass stay centred.
• Limiting, the last step, holding the peak level down while the average level comes up.

Dither belongs at the very end, when you reduce the bit depth for the final file. Master at the highest resolution you have.

Loudness targets on streaming

Every major platform normalizes playback, which means it measures your track and turns the volume down if you pushed it too far. The reference levels are minus 14 LUFS integrated on Spotify, the same on YouTube, minus 16 LUFS on Apple Music and minus 13 LUFS on SoundCloud. Bandcamp is the exception: it does not normalize at all.

First consequence: crushing a master to minus 8 LUFS does not make it louder on Spotify. It gets turned down, and the peaks are gone, so it plays back flatter than a more dynamic version of the same mix. Dynamic range is what survives normalization, not peak level.

Second: quieter tracks are not always raised. Amazon, Tidal and YouTube reduce the level when a master is too hot, but they do not push a quiet master up to the target, so a mix delivered at minus 20 LUFS simply sounds small there. Aim at roughly minus 14 to minus 10 LUFS integrated, with true peaks about a decibel below zero.

How to check your own master

Meters tell you two things you cannot hear reliably: integrated loudness and true peak. Load both on your master bus and run these checks before you upload.

• Leave headroom on the mix. Peaks between minus 10 and minus 3 dBFS give the mastering stage room to work.
• Compare at matched loudness. Level match against the reference before deciding which sounds better, or the louder file wins every time.
• Check in mono. If the snare loses its punch when you fold to mono, the stereo work went too far.
• Listen on the bad speakers. A phone and a car tell you more about your low end than studio headphones will.

DIY mastering, or pay an engineer

A mastering engineer brings a treated room and speakers they know. For a single release, a clean chain, a reference track and decent meters get most independent songs to a place where nobody notices. A trained ear is the honest reason to pay, not the plugins.

The shortcut: start from an instrumental that is already balanced

If you are rapping over a beat instead of producing it, you inherit its mix and its master, and plenty of home recordings sound amateur because the beat and the vocal never sat together in the first place. Pick an instrumental whose drums already sit where your flow wants them and whose low end leaves a hole for a voice.

Supreme, for example, is a hard anthem trap beat with brass stabs and 808s built exactly that way, so the vocal has somewhere to go before you touch a fader. The trap section and the full catalogue cover the rest of the range, and the licence terms tell you what you are allowed to do with the file.

Frequently asked questions

Can I master my own song at home?

Yes, and for a first release you probably should. Work with a chain rather than plugins picked at random, use a reference at matched loudness and check the result on more than one system.

What is the difference between mixing and mastering?

Mixing balances the individual elements into one stereo file. Mastering processes that finished file as a whole to control the tone, the dynamics and the final level, and to keep a release consistent across playback systems.

What loudness should I master to for Spotify?

Around minus 14 LUFS integrated, which is the level Spotify normalizes to, with true peaks about a decibel below zero. Going louder does not gain you volume there, it only costs you dynamics.

Is AI mastering good enough?

It is a fast way to reach a competitive level and a reasonable tonal balance, and it beats an untrained first attempt. What it cannot do is tell you the snare should have been quieter in the mix.

Should I master before or after recording vocals?

After. The master is applied to the finished song with the vocals in it. If you only have the instrumental today, master the completed version, not the beat.