Mastering checklist

Signed off by the artist and everyone involved. If the vocal level or a harsh guitar still bothers you, go back to the mix: mastering affects the whole song at once.

WAV or AIFF, 24-bit or 32-bit float, at the mix’s sample rate, with peaks between −6 and −3 dBFS and no limiter on the mix bus.

Master on another day than the mix, or have someone else do it. After days on a song, you stop hearing its flaws.

Two or three released songs in the same genre that sound like where you want to land. You’ll compare your master to them at the same loudness.

Streaming only, or CD and vinyl too? Each needs its own master or file: plan them now rather than after approval.

Once, from start to end, taking notes: what is too much, what’s missing, what must not change. These notes guide every decision.

Compare with the processing bypassed and the level matched; most mastering plugins have a button for it. Otherwise louder always wins, and you keep the wrong settings.

Moves of a dB or two, on wide bands. If you need a big boost or a narrow cut, the problem is in the mix: ask for a new mix or for stems.

A dB or two of compression to glue, not more. The chorus should still hit harder than the verse.

Keep the bass and kick in the center, and widen carefully: what you push into the sides gets lost in mono and on single-speaker devices.

Push it until you hear it pump or distort, then back off. On streaming, louder isn’t louder for the listener: at its default setting, Spotify turns a −8 LUFS master down by 6 dB, along with the punch it lost to get there. Source: Spotify for Artists

Over the whole song, with a loudness meter. Spotify plays songs at −14 LUFS by default and Apple Music at around −16 LUFS: you don’t have to hit these numbers, but a much louder master will simply be turned down.

Measured with a true peak meter: peaks between samples can distort once the song is encoded for streaming. Spotify recommends −2 dBTP for masters louder than −14 LUFS. Source: Spotify for Artists

Listen to the master encoded in AAC or MP3, as most listeners will hear it. Apple’s free afclip and AURoundTripAAC tools, included in macOS, reveal the clipping that encoding causes. Source: Apple Digital Masters

A phase correlation meter that stays mostly positive, and a mono listen where the vocal, snare and bass hold up.

Phone, earbuds, car, laptop, at low and high volume: the balance should hold everywhere, and the low end should stay under control on large speakers.

From start to end, doing nothing else: clicks, digital distortion, noise in the fade, a reverb tail cut short.

No click on the first note, a short silence before it, and a fade-out that reaches true silence instead of cutting off the tail.

WAV, 24-bit at 44.1 kHz or higher, as your distributor asks. When reducing the bit depth, for example to 16-bit for CD, dither once, as the very last step.

For CD, a DDP image with the track order, gaps, ISRC codes and CD-Text. For vinyl, a separate, less limited master with tamed sibilance and a centered low end, prepared with the cutting engineer.

Instrumental, clean, a cappella, mastered with the same settings as the main version so they can be swapped in an edit or a sync placement.

Artist – Song – Master.wav for the final file, previous versions in a separate folder: nobody uploads the wrong master.

By the artist, on the systems they know, after a break. Note every revision request with the moment in the song it refers to.

Final files, premaster and mastering session or preset, backed up in two places. A vinyl, a remix or a remaster will start from there.