A carefully prepared mix gives the mastering engineer the best possible starting point and helps protect the quality of your music throughout the final mastering process.
You may have spent days, weeks or even months refining your mix. Before sending it for mastering, it is important to check the audio, choose the correct file format and organise the delivery clearly.
This guide explains how to prepare your audio files for professional mastering in six straightforward steps.
Recommended Mastering File Specifications #
These settings provide a reliable starting point for most professional mastering projects.
Uncompressed full-quality audio.
Use the native resolution of the mix session.
Do not change the sample rate unnecessarily.
Sensible headroom is more important than an exact number.
Unless it is an essential part of the sound.
Include references and project information.
How to Prepare Files for Mastering #
Check and Finalise Your Mix #
Before exporting the mastering file, listen through the complete mix from beginning to end. The mix should be creatively finished and approved before it reaches the mastering stage.
Listen carefully for unwanted noises, edits, automation errors, clipped peaks or effects that end too abruptly. It is also worth checking the start and end of the track for accidental silence or noise.
Choose WAV or AIFF #
WAV and AIFF are the most common formats for professional mastering because they can store uncompressed, full-resolution audio.
Either format is suitable when exported at the correct sample rate and bit depth. There is no meaningful sound quality difference between equivalent WAV and AIFF files.
Keep the Original Sample Rate and Bit Depth #
Export the mix at the same sample rate used during the recording and mixing session. There is usually no benefit in changing a 44.1 kHz session to 96 kHz during the final export.
A bit depth of 24-bit is suitable for most mastering deliveries. A 32-bit floating-point file may also be accepted when it is supported by the mastering workflow.
Leave Clean, Unclipped Headroom #
The mastering file must not clip. Leave enough space below 0 dBFS so that the loudest peaks remain clean and undistorted.
A peak level somewhere around −3 to −6 dBFS is commonly suitable, but the mix does not need to be forced to exactly −6 dBFS. Clean peaks and a healthy mix balance are more important than meeting one fixed number.
Organise and Name Your Files Clearly #
Clear file organisation reduces confusion and helps the mastering session begin efficiently. Each file name should identify the artist, track and version.
Artist_Name_Track_Title_Mix_01_24bit_48k.wav
Artist Name #
Include the artist or project name.
Track Title #
Use the correct final title for each song.
Version #
Identify the mix revision or alternate version.
Technical Details #
Add the sample rate or bit depth when helpful.
Include the following project information #
- Artist and project name
- Final track listing and running order
- Correct song titles and spelling
- Preferred gaps or transitions between tracks
- Catalogue codes or ISRC information where applicable
- Notes describing any alternate or instrumental versions
- Reference songs or previous mix versions
- Your preferred delivery formats
Upload and Submit Your Files #
Once the mix files have been checked, exported and clearly labelled, they can be submitted for mastering.
Confirm the preferred upload method before sending a large project. Files may be delivered through a secure transfer service, cloud folder or dedicated client portal.
Common File-Preparation Mistakes #
Avoiding these problems can prevent unnecessary delays, revisions and quality loss.
Sending Only an MP3 #
Always provide the original full-resolution WAV or AIFF file wherever possible.
Clipping the Mix #
Peaks that exceed the available digital level may already contain distortion that mastering cannot remove.
Unnecessary Upsampling #
Exporting a 44.1 kHz session at 96 kHz does not restore information that was never recorded.
Heavy Final Limiting #
Excessive limiting can remove the dynamic space required for effective mastering.
Confusing File Names #
Names such as “final-final-new-2.wav” make version control unnecessarily difficult.
Missing Reference Information #
Include notes, references and instructions that explain the intended sound and delivery.
Mastering File Checklist #
Preparing Files for Mastering #
What file format should I send for mastering?
Send an uncompressed WAV or AIFF file. Export it at the native sample rate and bit depth of your mix session.
How much headroom should I leave for mastering?
The mix must remain below 0 dBFS without clipping. Peaks around −3 to −6 dBFS are commonly suitable, but there is no requirement to force the mix to one exact peak level.
Should I remove all processing from the master bus?
Keep processing that forms an essential part of the sound. Remove loudness limiters or clippers where possible and provide an alternative version when you are uncertain.
Should I export the mix at 44.1 kHz or 96 kHz?
Export at the sample rate used by the original mix session. Do not increase the sample rate only for the mastering export.
Can I send a 32-bit floating-point file?
Yes, when supported by the mastering workflow. A 24-bit WAV or AIFF file is also suitable for most professional mastering projects.
Can an MP3 be mastered?
An MP3 can be processed, but it has already lost audio information through compression. The original WAV or AIFF mix will provide a better mastering source.
Good Preparation Protects Your Music #
Correct file preparation is a simple but important part of the mastering process. It ensures that the mastering engineer receives a clean, full-resolution source without unnecessary technical limitations.
By checking the mix, using WAV or AIFF, keeping the original sample rate, avoiding clipping and organising the project clearly, you provide the strongest possible foundation for the final master.
Finalise and carefully check the complete mix
Export a full-resolution WAV or AIFF file
Leave clean headroom without clipping
Clearly organise and identify every file
