The Mastering Guide
Mastering is the last step — taking a finished mix and making it loud enough, tonally balanced, and consistent so it holds up on every system, from AirPods to a car to a club. It's a game of small moves — a decibel here, a hair of glue there. This guide draws what those moves do and gives you the exact Logic Pro X tools for each.
What Mastering Is (and Isn't)
Mastering is the bridge between your mix and the world. It does three jobs: raise the track to competitive loudness, apply a final tonal balance so it translates everywhere, and — across an album — make every song feel consistent. What it isn't: a rescue mission. Mastering polishes a good mix a few percent; it can't fix a muddy or unbalanced one. Fix those in the mix and come back.
The whole art is the middle picture. Since every streaming service now normalizes loudness, the loudness war is over — smashing a track flat just costs you punch and gets turned down to the same level as everyone else. Dynamics are a feature, not a bug.
Before You Master
The best masters start with the right handoff from the mix. Ideally master with fresh ears on a different day — mastering is a decision job, and tired ears make loud, bad decisions.
Leave Headroom
Bounce the mix peaking around −6 dB (no limiter on the mix bus). The master needs room to work — a mix already slammed to 0 leaves nothing to shape.
Fix It in the Mix
If something's wrong — harsh, boomy, a buried vocal — go back and fix the mix. Mastering EQ is broad; it can't surgically undo a mix problem without hurting everything else.
Bounce a Clean File
Export a high-resolution 24-bit WAV at the project sample rate. Master that flat file in a fresh project, not on your busy mix session — you'll judge it more honestly.
Line Up References
Pull 2–3 commercial songs in the same style. They're your target for tone and loudness — gain-match them so you're not fooled by their level.
Raise the Buffer
Mastering plugins are CPU-heavy and you're not recording, so latency doesn't matter — set the I/O Buffer Size to 512 or 1024 for glitch-free playback. It never touches the bounce (that's rendered offline). Full explainer in the Logic buffer & latency guide.
The Mastering Chain
A master is a short, deliberate chain of gentle processors. Each does a little. The order matters — clean up, glue, shape, color, widen, then raise the level last with the limiter, watching a meter the whole way.
Some engineers put a broad subtractive EQ before the compressor (so boomy lows don't pump it) and a tonal EQ after (to shape the glued result) — exactly like a mix chain, just gentler. The limiter is always last: it sets the final ceiling nothing may cross.
EQ, Compression & Width
On the whole mix, every move is broad and small. You're nudging the balance of the entire song at once, so a 1 dB shelf is a big move and a 3 dB boost is enormous. Reach for wide, gentle curves and low ratios.
Tonal EQ
Gentle, wide moves for the whole-mix balance: a touch of low-end weight, a dip where it's harsh (2–4 kHz), a shelf of "air" up top. Think ±1–2 dB, low Q. A subtle high-to-low tilt fixes most tonal imbalances.
Glue Compression
One gentle bus compressor for cohesion — low ratio (1.5–2:1), slow attack, auto/slow release, only 1–2 dB of gain reduction on peaks. You want it to breathe with the song, not squeeze it. More on how compression works in the Recording Guide.
Multiband — Surgically
When one band misbehaves (boomy lows pumping, harsh highs spiking), a multiband compressor tames just that range without touching the rest. Use it as a scalpel, not a default.
Saturation
A whisper of tape or tube adds density, warmth, and harmonic "loudness" that survives normalization. Drive it gently — on a full mix, a little is a lot.
Stereo Width
Widen the sides for openness with a Mid-Side tool — but keep the bass mono. Wide lows smear and can cancel on club systems & vinyl. Widen the top, anchor the bottom.
Mid-Side EQ
Master-grade trick: EQ the mid (center — vocal, kick, bass) separately from the side (width — cymbals, reverb, guitars). Add air to the sides, clarity to the mid, independently.
Loudness & the Limiter
The limiter is a brick wall: it sets a ceiling nothing crosses, then lets you push the whole track into it to raise the average level. Push gently — the goal is competitive loudness with the peaks shaved, not a flattened sausage. Below, the same signal hitting the ceiling: peaks over the line get caught, everything else passes.
How loud? Loudness is measured in LUFS (perceived loudness) and peaks in dBTP (true peak). Streaming platforms normalize everything to a target, so mastering past it just gets turned down — losing dynamics for nothing. Aim for the target and keep true peak at −1 dBTP to survive lossy encoding.
| Platform | Normalizes to | Notes |
|---|---|---|
| Spotify | −14 LUFS | Louder masters get turned down to this |
| Apple Music | −16 LUFS | Sound Check; the quietest target |
| YouTube | −14 LUFS | Turns loud masters down, never up |
| Amazon / Tidal | −14 LUFS | Same ballpark |
| Club / DJ / CD | −9 to −6 LUFS | No normalization — loudness still matters here |
| True-peak ceiling | −1 dBTP | Set this on the limiter, always |
A practical target: master to around −14 to −10 LUFS integrated with a −1 dBTP ceiling and it'll translate well everywhere. Don't chase a number at the cost of the music — if 2 dB of loudness costs you all the punch, it's a bad trade. Let the song's energy, not the meter, decide the last dB.
Metering, Reference & the Bounce
Loudness fools your ears in seconds — meters don't. Master with a LUFS meter open, check your true peak, watch a spectrum against your references, and confirm the stereo image is mono-safe. Then commit with a clean, dithered bounce.
Loudness Meter
Read Integrated LUFS (whole-song loudness — your target number), Short-term (moving), and True Peak (must stay under −1 dBTP).
Spectrum & Reference
A/B your master against commercial references at matched loudness — a real-time analyzer shows if you're too dark, too bright, or bass-heavy versus the target.
Correlation / Mono
Watch the correlation meter and check the whole thing in mono. If the low end vanishes or the image collapses, pull your width back.
Dither on Export
Only when reducing bit depth (e.g. 24-bit → 16-bit for CD), add dither on the final bounce to mask quantization noise. Streaming/24-bit? No dither needed.
Check Everywhere
Bounce it and listen on phone, laptop, car, earbuds. A master that holds up on a phone speaker holds up anywhere — that's the whole point.
Walk Away, Then Decide
Sleep on it. The master that sounded perfect at 1 a.m. often needs a hair less limiting in the morning. Fresh ears are the best mastering tool there is.
Mastering is restraint under a microscope — the smallest moves on the whole song, judged against the best in the world at matched loudness. Get the mix right, make a few gentle moves, respect the meters, and stop before you squeeze the life out. That last 2 dB is where a track goes from "done" to released.