Preparing a song correctly before sending it to a mixing or mastering engineer may not be the most exciting part of making music, but it can have a significant effect on both the process and the final result.

Good preparation allows the engineer to spend more time making creative and technical decisions, rather than trying to identify missing files, repair incorrect exports, work out which version is current, or rebuild elements of the original session.

It can also reduce delays, avoid unnecessary revisions and help ensure that the song reaches the engineer exactly as the artist intended.

Mixing and mastering require different types of preparation, so it is important to understand what should be supplied at each stage.

Preparing a Song for Mixing

When a song is being sent for mixing, the engineer will usually need each recorded or programmed element as a separate audio file. These files are often referred to as multitracks.

The goal is to provide a complete, clearly organised set of audio files that can be imported into a new session and played back correctly without requiring access to your original DAW project.

  1. Make sure every track starts from the same point

All files should be exported from the same starting position, usually bar 1, beat 1, even if a particular instrument does not begin until later in the song.

For example, if a backing vocal first appears during the final chorus, its exported file should still begin from the same point as the kick drum, bass, lead vocal and every other track.

This allows the engineer to import all files together and have the entire arrangement line up automatically.

Your export range should also cover the full length of the song, including any reverb tails, delays, cymbal decay or other sounds that continue after the final note.

  1. Export using the correct audio format

WAV or AIFF files are recommended for professional mixing.

Ideally, the files should be exported at the same bit depth and sample rate used during recording. A common professional format is 24-bit, 48kHz, although 24-bit, 44.1kHz is also acceptable and higher sample rates are fine.

Avoid converting files to MP3 or another compressed format. Lossy formats permanently remove audio information and are not suitable as the main source files for a professional mix.

There is also no advantage in artificially converting a 44.1kHz recording to a higher sample rate before delivery. Maintaining the original session format is generally the safest approach.

  1. Render all MIDI and virtual instruments to audio

Any virtual instruments, programmed drums, software synthesisers or MIDI-based parts should be bounced to audio before delivery.

This avoids compatibility issues caused by different software, missing sample libraries or unavailable plugins.

Stereo instruments should be exported as stereo files, while genuinely mono sources should remain mono. A mono lead vocal, bass guitar or close drum microphone does not need to be exported as a stereo file.

Before exporting, listen carefully to every rendered virtual instrument to make sure that notes, articulations, sustain, automation and effects have been captured correctly.

  1. Decide which effects should remain

As a general rule, tracks should be supplied dry unless an effect forms an essential part of the sound.

Temporary reverb used only to help a singer perform can usually be removed. However, a guitar sound created through pedals and an amplifier, a deliberately distorted vocal, a rhythmic delay or a unique production effect may be fundamental to the arrangement.

When there is any uncertainty, provide two clearly labelled versions:

This gives the mix engineer flexibility while preserving your creative direction.

It is also helpful to explain which version you prefer and why the effect matters to the song.

  1. Centre the panning and maintain sensible levels

Individual mono tracks should generally be exported with their panning set to the centre. The mix engineer can then place them appropriately within the stereo image.

Stereo sources containing intentional internal panning, such as stereo drum overheads, piano, keyboards or a designed stereo effect, can remain as they are.

Export levels should be healthy without clipping. A general target of approximately -12 to -18 dBFS per track is usually suitable, although this does not need to be treated as a rigid rule.

The important points are that the files are not clipping, are not unnecessarily quiet and retain their natural dynamics.

  1. Remove processing from the master bus

Before exporting multitracks for mixing, remove limiting, compression, EQ and other processing from the master output.

Master-bus processing affects the combined mix rather than the individual tracks, so it will not translate properly when each file is exported separately.

It is still useful to provide your rough mix with that processing left intact if it represents the sound you have been working towards. The rough mix gives the engineer valuable context, while the clean individual files provide the flexibility needed to build the final mix correctly.

  1. Label every file clearly

Clear file naming can save a surprising amount of time.

Number the files and use simple, descriptive names such as:

Avoid names such as “Audio 14”, “Final Vocal New”, “Guitar Copy 3” or other labels that require guesswork.

Where several singers or instruments are involved, include the performer or role in the name. For example, “Sarah Lead Vocal”, “Tom Harmony Low” or “Chorus Gang Vocal”.

  1. Check the files in a fresh session

This is one of the most important steps in the entire preparation process.

Create a new, empty session and import every exported file from the same starting point. Then listen through the complete song.

Check that:

Do not assume an export is correct simply because the original session played properly. Problems can occur during bouncing, freezing, consolidating or transferring files.

  1. Include a rough mix and reference tracks

Your rough mix is extremely useful, even if you know it is not technically polished.

It shows the engineer how you have been hearing the balance, where instruments were positioned, which production elements are important and what emotional direction you intended.

Two or three professionally released reference tracks can also help communicate qualities such as vocal placement, low-end weight, overall energy, width, brightness or level of polish.

References should guide the conversation rather than serve as tracks that must be copied exactly. Every song contains different performances, arrangements, tones and recording conditions, so an exact match is rarely realistic.

  1. Organise the final delivery

Place all files into one clearly labelled folder containing the artist name, song title and BPM.

A practical structure might include:

Compress the main folder into a ZIP file and upload it through a reliable service such as Dropbox, Google Drive, OneDrive or WeTransfer.

Any notes should clearly identify the approved song structure, important effects, edit requests, preferred references and anything unusual the engineer needs to understand before beginning.

Preparing a Song for Mastering

Mastering preparation is different because the mixing stage should already be complete.

Rather than supplying every individual track, the artist usually provides the final stereo mix. The purpose of mastering is to refine that finished mix, optimise translation and prepare it for release.

  1. Confirm that the mix is genuinely final

Mastering should not be used as a substitute for unfinished mixing.

Before delivery, carefully check:

Once mastering begins, changes to individual instruments are limited because they are already combined within the stereo mix.

If the vocal is too quiet, the snare is too loud or an edit is incorrect, the best solution is usually to return to the mix rather than attempt to force a repair during mastering.

  1. Supply a high-quality stereo file

Provide the final mix as a 24-bit WAV or AIFF file, ideally using the original session sample rate.

Common sample rates include 44.1kHz and 48kHz, although higher sample rates are also acceptable.

Do not convert the final mix to MP3, and do not change the sample rate unless there is a specific technical reason to do so.

  1. Avoid clipping, but do not force artificial headroom

A mastering engineer does not require an arbitrary amount of empty headroom.

You do not need to reduce a healthy mix to an unusually low level simply to meet a rule such as “leave exactly 6 dB of headroom”.

What matters is that the output is clean and not clipping.

A well-balanced, dynamic mix that peaks relatively close to zero can still be completely suitable for mastering, provided it has not been damaged by clipping or excessive limiting.

  1. Consider your limiter and master-bus processing carefully

In most cases, it is helpful to supply one version without a limiter on the master bus. This often gives the mastering engineer greater control over dynamics, level and final tonal balance.

However, if your limiter, bus compressor, tape emulation, saturation or other stereo processing forms an important part of the sound, do not simply remove it without considering the effect.

A good approach is to provide:

Clearly label both files and explain which processing was used intentionally.

Avoid excessive limiting, clipping, compression or stereo widening unless it is genuinely part of the artistic direction, as heavy processing can reduce the options available during mastering.

  1. Check the beginning, ending and fades

Listen from several seconds before the song begins until well after the final sound has decayed.

Make sure the opening is not cut off and that the ending includes the full natural decay of instruments, reverbs and delays.

If you have a specific fade in or fade out, either print it exactly as intended or supply clear instructions.

It is better to provide a little extra audio at the beginning and end than to cut the file too tightly.

  1. Provide complete and accurate information

Clearly label the file and include relevant details such as:

For an EP or album, also provide the final track order and note any intended spacing, crossfades or transitions between songs.

If a DDP master is required for CD duplication, the final sequence and spacing information should be confirmed before the DDP is created.

  1. Prepare stems correctly when booking stem mastering

Stem mastering involves supplying groups of instruments rather than one stereo mix.

Typical stems may include drums, bass, guitars, keyboards, lead vocals, backing vocals and effects.

Every stem must:

After exporting, import the stems into a new session at unity gain and confirm that they reproduce the intended balance.

  1. Supply appropriate references

Reference tracks are also helpful for mastering.

They can communicate the tonal balance, density, perceived loudness, brightness, low-end character or general finish you are aiming for.

It is particularly useful to explain what you like about each reference rather than simply sending a list of songs. For example, you may like the vocal clarity of one track, the low end of another and the overall dynamics of a third.

A Few Final Checks Before Delivery

Whether you are preparing files for mixing or mastering, ask yourself the following questions before sending anything:

  1. Is this definitely the approved version?
    Confirm that collaborators, band members or other decision-makers have signed off before professional work begins.
  2. Have I listened to the actual exported files?
    Do not rely solely on playback from the original DAW session.
  3. Are the files clearly labelled?
    The engineer should not need to guess which version is current.
  4. Have I explained anything unusual?
    Intentional distortion, unusual edits, alternate tunings, tempo changes and creative effects should be identified.
  5. Are my references realistic and relevant?
    Choose tracks that relate meaningfully to your genre, arrangement and intended aesthetic.
  6. Am I ready to commit to the song?
    Professional mixing and mastering work best when the songwriting, performance, production and arrangement decisions are already settled.

Final Thoughts

Proper preparation is not about following rules for the sake of it. It is about protecting the music and making sure the engineer receives an accurate representation of the song you created.

Well-prepared files allow the process to begin with clarity. They reduce technical interruptions, preserve creative momentum and give the engineer more time to focus on balance, emotion, translation and impact.

The better the preparation, the more productive the collaboration is likely to be.

And if you are unsure whether your song, mix or files are ready, it is always better to ask before sending them. A quick conversation or pre-mix assessment can often identify issues early and prevent unnecessary delays later in the process.

Until next time,

Mike