How to prepare a mix for mastering: a 7-point checklist
updated · November 2, 2026 · by Alex Pritsert
To prepare a mix for mastering, export a clean stereo file that peaks around -6 to -3 dBFS, with any loudness limiter removed from the master bus. Use 24-bit WAV or AIFF at your session's sample rate, keep the fades natural, and fix clicks, hum and balance problems before you bounce.
Short answer
Most of what makes a master disappointing was already in the file. Leave room at the top: a mix that peaks between -6 and -3 dBFS gives EQ, compression and limiting space to work. If your master-bus limiter is only there for loudness, take it off before the export, and keep a loud copy as a reference for yourself.
Export at your session's sample rate in 24-bit WAV or AIFF, without normalizing. Listen for clicks, hum and harsh vocals, since mastering makes them louder. Check the mix in mono, because anything that disappears will disappear on some phone speakers too. Then label the file so you can tell which version you sent. None of these steps takes long, and together they leave whoever masters the song with far more options.
The checklist at a glance
This checklist is for producers about to bounce a mix and send it to an engineer, an online service or their own mastering software. The steps are the same in each case, and they take about ten minutes.
| Check | Aim for | Why |
|---|---|---|
| Peak level | About -6 to -3 dBFS | Leaves room for processing |
| Master bus | No limiter added only for loudness | Keeps dynamics available |
| Format | 24-bit WAV or AIFF, session sample rate | Avoids a lossy or converted source |
| Start and end | Natural fades, a little silence | Protects tails and transients |
| Clean-up | No clicks, hum or clipping | Mastering makes them louder |
| Mono | Nothing important vanishes | Phones and club systems |
| File name | Song, version, date | Prevents mastering the wrong mix |
1. Leave headroom: how many dB is enough?
MasteringBOX suggests peaks between -6 and -3 dBFS and treats -6 as a working guideline, adding that a clean mix at -4 or -3 is fine. iZotope's mixing guide gives the reason: high-pass filters, EQ moves and compression can all raise peak levels, so some room should remain when mastering starts.
If your mix already peaks at 0 dBFS and isn't clipped, you don't need to remix it. Pull the master fader down until the peaks sit in that range. Digital gain in a modern session is transparent, so nothing is lost. If the file has already clipped, lowering it afterwards won't remove the damage, so go back to the session and bounce again.
2. Take the loudness limiter off the master bus
A limiter added only to make the mix sound competitive squashes the transients that mastering needs. Once they are gone, no later stage can restore them. MasteringBOX recommends removing it and exporting two files: a clean premaster and a loud reference that shows the sound you were aiming for.
There is an exception. If bus compression or saturation is part of the sound you built, keep it. The test is simple: bypass it. If the mix falls apart, it belongs to the mix. If the mix only gets quieter, it was there for loudness.
3. Export the right file format
Bounce to 24-bit WAV or AIFF at the sample rate of your session. Don't export an MP3 for mastering, because lossy encoding has already thrown away audio that can't be recovered. Leave normalization off, since it moves your level without telling you, and leave dither for the final delivery file.
4. Keep fades and silence natural
Don't trim tightly around the first transient or the last reverb tail. A little silence at each end lets the mastering stage work on the whole sound without cutting anything off. If a fade-out is part of the song, write it in the mix. A limiter responds to the level going into it, so a fade applied before limiting behaves differently from one applied afterwards.
5. Remove what mastering would make louder
Compression and limiting raise the quiet parts of a track, including hum, room noise and the click you stopped hearing weeks ago. Sibilance gets harsher too. These are far easier to fix on the track they came from than on the finished stereo file.
Tunr's analysis can help you catch them. It reports noise floor, clicks, hum, sibilance and clipping, each with its numbers, and it suggests clean-up only when the analysis is confident. If it flags clicks in the mix you thought was finished, going back to the session is usually the better repair. AI-generated songs need extra care here, which we cover in how to master Suno and Udio tracks.
6. Check the mix in mono
Sum the mix to mono and listen for anything that thins out or vanishes. Wide synths and stereo-widened vocals are the usual casualties. Plenty of phone speakers and venue systems will play your song this way, whatever your monitors show. Tunr's A/B Mixer can solo stereo, mono, mid or side, and the master report includes stereo correlation, which drops as the two channels stop agreeing.
7. Label the file
Name the file with the song, version and date, for example nightdrive_mix-v7_2026-11-02.wav. Keep a line of notes with it: the target platform, any reference song, and anything you want left alone. That's the point where you can master the track or send it off with confidence you sent the right one.
Frequently asked
What level should my mix be before mastering?
Aim for peaks between about -6 and -3 dBFS. The exact number matters less than having room and no clipping, so a clean mix at -3 is fine. Integrated loudness at this stage doesn't need to hit any target, because mastering is the step that sets the final level.
Should I leave a limiter on my mix before mastering?
Usually not, if it is there only for loudness, because it removes transients a later stage can't restore. Keep bus processing that shapes the sound of the mix. Exporting two files, one clean premaster and one loud reference, shows your intent while leaving the mastering stage free to work.
What sample rate and bit depth should I export for mastering?
Export at the sample rate your session already uses, in 24-bit WAV or AIFF, without converting it. Sample-rate conversion and dither belong at the delivery stage, when the final files are made. Avoid MP3 or AAC as a source, because lossy encoding removes audio that mastering can't bring back.