How to Prepare Your Mix for Mastering: A Complete Delivery Guide

Mastering can make a finished mix translate better, feel more consistent, and sit properly beside other released music. What it can’t do is magically turn an unfinished mix into the version you had in your head.

That’s why delivery matters.

If you’re mixing your own track, the goal is simple: send a clean, approved, high quality mix that lets the mastering engineer enhance what’s already there. A good master starts with a mix that feels right before it ever leaves your DAW.

A finished mix should feel approved before it goes to mastering.

Send an approved stereo WAV file

For standard stereo mastering, send a high quality stereo WAV file of the final mix. That means the version you’ve listened to, checked, and approved.

The mastering stage is not the best place to fix a vocal that’s too quiet, a snare that disappears, or a synth that takes over the chorus. It can sometimes help those things a little, but mastering is mainly about tone, level, dynamics, translation, and preparing the track for release.

A good delivery file is usually:

• A stereo WAV file

• The same sample rate you mixed at

• The same bit depth you worked at

• Not clipping, unless clipping is a deliberate part of the sound

• Clearly named

  
  

Don’t convert the file yourself unless you’ve been asked to. If your session is at 48 kHz and 24-bit, send that. If it’s at 44.1 kHz and 32-bit float, send that. The mastering engineer can handle the sample rate or bit depth changes needed for streaming, CD, or other formats.

For context, CD audio uses 44.1 kHz and 16-bit, while streaming services accept a range of formats depending on the distributor. Vinyl has its own physical limits, especially in the low end and high frequency content. More on that in a minute.

Make sure the bounce starts and ends cleanly

This sounds boring, but it saves a lot of hassle.

Before sending the mix, listen to the full exported file from start to finish. Don’t just check the DAW session. Actually play the WAV you’re about to send.

Check that:

• The first transient hasn’t been clipped

• There isn’t unwanted count-in, click, or noise at the start

• The ending doesn’t cut off a reverb tail or delay repeat

• Any intended fade-out feels natural

• There are no pops, glitches, or export errors

  
  

A reverb tail getting chopped short is one of those tiny things that jumps out once the track is mastered, because the final master often brings up detail and ambience.

Always check the exported WAV, especially the ending.

Don’t worry too much about the 6 dB headroom rule

You might have seen advice saying you must leave at least 6 dB of headroom before mastering. That advice was useful in some older workflows, but it’s not a fixed rule now.

The main thing is this: don’t clip the output.

In digital audio, 0 dBFS is the maximum level. If the mix is hitting above that and causing unwanted distortion, that’s a problem. If the loudest peak is at -0.5 dBFS, -3 dBFS, or -6 dBFS, that’s usually fine as long as it sounds clean.

There’s one exception. If distortion, clipping, or heavy limiting is part of the sound and you love what it’s doing, say so. Some genres use pushed mix buses as a creative choice. The key is making sure it’s intentional, not accidental.

So, if you’re trying to prepare mix for mastering, don’t pull the whole mix down just to hit a number. Send the best sounding version that isn’t accidentally clipping.

Decide what to do with mix bus processing

Mix bus processing can be tricky because it might be doing a lot of the work.

If you’ve mixed into a compressor, EQ, tape plugin, clipper, or limiter from the start, removing it might change the balance and feel of the track. The kick might sit differently. The vocal might jump forward. The chorus might stop feeling exciting.

So here’s the practical approach:

If the mix bus processing is crucial to the sound

If it’s only there for loudness

If you’re unsure

Send the processed version, and ideally send an unprocessed version too

Send a version without the limiter or loudness processing

Send both versions and explain what each one is

It can also help to send a screenshot or list of the mix bus plugin chain. If the processing is part of the character, the mastering engineer can use that as a starting point and make small changes to improve dynamics, clarity, or translation without losing the intention.

Mix bus choices matter because they shape the final sound.

Send all versions together if you can

If you need extra versions, send them at the same time as the main mix. That helps keep the mastering decisions consistent across the whole release.

Common extra versions include:

• Instrumental

• Clean version

• Radio edit

• Extended mix

• Acapella

• TV mix

  
  

Make sure each version uses the same mix settings where possible. For example, if the instrumental has a different limiter setting or a changed vocal reverb send that affects the music, it may not match the main master as well.

Clear file names help too. Something like:

`Artist - Song Title - Main Mix - 48k 24bit.wav`

`Artist - Song Title - Instrumental - 48k 24bit.wav`

That’s much easier to work with than `final_mix_7_REALFINAL.wav`.

Say what the master is for

Tell the engineer where the track is going.

Streaming, CD, download, and vinyl can all shape the final delivery choices. The differences might be subtle, but they matter.

Vinyl is the big one. Very wide low end, harsh high frequencies, or extreme sibilance can cause problems when cutting a record. That doesn’t mean a vinyl master has to sound dull or small. It just means the format has physical limits that don’t exist in the same way on streaming platforms.

It also helps to mention if the track is part of an EP or album. Tracks that sit together may need level and tonal matching, not just individual treatment.

References can be useful, but they’re usually more useful in production and mixing than in mastering music. Still, if there’s a track that captures the level, brightness, low end, or mood you’re aiming for, send it over. Just remember that the master still has to suit your mix, your arrangement, and your release format.

Ask for a stem master if the mix still needs help

If you’re not happy with the mix but want to see what mastering can do, ask about a stem master.

Instead of sending one stereo mix, you send high quality WAVs of grouped elements. For example:

• Drums

• Bass

• Music

• Lead vocal

• Backing vocals

• Effects

  
  

This gives more control over levels and processing without opening the full mix session. It can help if the vocal is slightly too low, the kick is too heavy, or the guitars are clouding the chorus.

A stem master isn’t a replacement for a full mix, but it can be a good middle ground when the track is close and needs a little more control than a stereo file allows.

Stem mastering can help when the mix needs small balance changes.

Talk to your mastering engineer before sending files

If you’re in doubt, ask first. A short message can save a messy export, a wrong format, or a second round of file transfers.

A simple delivery note might include:

• The final mix WAV

• Any alternate versions

• The sample rate and bit depth

• Whether mix bus processing is printed

• The intended release format

• Any references

• Any concerns about the mix

  
  

If you need help getting a track ready for release, you can get in touch about mastering here.

The short version is this: send the best approved mix you have, don’t clip it by accident, keep the start and end clean, and explain what the release needs to be. Mastering works best when the direction is clear and the mix already feels like the record.