How to prepareyour trackfor mastering.

Finalize Your Mix

Mastering starts with a mix you are ready to approve. Make the important decisions about vocals, drums, bass, instruments and effects before sending it. If the chorus feels unbalanced or the vocal still needs editing, address that in the session rather than expecting mastering to rebuild the song.

Listen for the relationship between the low end, midrange and treble, and for the movement between quieter and louder passages. Keep the project organised so you can return to a specific part if an adjustment is needed. For stereo mastering, however, the file you send is the combined mix, not the individually labelled channels.

Separate creative mix-bus processing from final loudness processing. Compression, EQ or saturation may be part of the sound you mixed into. Do not automatically remove those decisions. Bypass a brickwall limiter or maximiser added solely to raise the listening level; if it is essential to the character, send both versions and explain which sound you prefer.^[2]

Check sibilant vocals, distracting resonances and abrupt edits at their source. A small correction on one track is often more controlled than processing the complete stereo mix later.

Optimize Your Project

Preparation should protect the mix, not turn into a new mastering session. Concentrate on clean edits, reliable exports and sensible levels.

Clean Up Tracks

Listen around edits, starts, stops and quiet passages. Remove unwanted clicks, hum or accidental sounds where they occur. Use short fades or crossfades where needed to smooth an edit, without cutting off a transient or the natural decay of a note.

Noise reduction is a repair tool, not a compulsory step on every recording. Apply it only to an audible problem, compare the result with the original, and check that it has not dulled the recording or damaged quiet details. Likewise, disable a plug-in’s analogue-noise option when it adds unwanted hiss, not simply because the option exists.

Keep intentional ambience, breaths and production texture. Trim accidental empty space, but leave enough room for the opening sound and the full ending. Flag deliberate long pauses, fades or transitions in your notes.

Set Proper Levels

The priority is an unclipped mix with its intended dynamics intact. For Product London, peaks around −6 to −3 dBFS are a practical guide; neither −10 dBFS peaks nor a fixed −18 dBFS average is a universal submission requirement.^[1]

A clean mix can be turned down without rebuilding its balance. That is different from turning down a file that already contains distortion or flattened peaks: a lower meter reading does not undo earlier clipping or heavy limiting.

Check the loudest passage and the entire export, not just the intro. Keep enough room to avoid accidental overs, but do not radically change your mix just to hit a particular number.

Export Options

Use these settings for a standard stereo pre-master sent to Product London. The export should contain the mix you approved, at its original sample rate, without an extra loudness boost.

Interleaved stereo means that both channels are stored in one file. It does not retain access to the separate vocal and instrument tracks. If those still need balancing independently, the relevant service is audio mixing.

Normalisation and Dither

Peak normalisation changes the gain of the whole file; it is not compression. On its own, with no added clipping or limiting, it does not reduce the difference between quiet and loud passages. Leaving it off makes this export simpler to assess; it is not a claim that every normalised file has damaged dynamics.^[3]

Dither concerns bit-depth reduction, not whether a file happens to be called a master. Leave it off for a 32-bit float export. When rendering to 24-bit PCM, follow your DAW’s guidance; plain, non-noise-shaped dither may be appropriate. Do not apply two dither stages to the same export. Reserve noise-shaped final-delivery presets for the appropriate final conversion.^[4][5]

Keep the original sample rate unless a different one has been requested. This avoids an unnecessary conversion before mastering; it does not mean that properly performed sample-rate conversion always causes audible damage.^[5]

Metadata Considerations

Clear identification matters more at handover than filling every possible embedded tag. Include your artist name, track title, exact mix version and contact details. For an EP or album, also provide the release title, intended track order and notes about gaps or continuous transitions.

A simple, consistent filename makes the approved version easy to identify:

Use the values that actually describe your file. Label alternate mixes separately and make clear which is the one to master. Avoid sending several files all called “final” without an explanation.

If ISRCs or other release identifiers have already been assigned, include them in a track-information document. An ISRC identifies a recording; it is not an audio-quality setting.^[6]

You can send the mix for review without first embedding artwork, ID3 tags or release codes into the pre-master. Share available release metadata in your notes and agree any final-format requirements separately. Do not invent identifiers or assume embedded tags replace the information requested by your distributor.

Final Mix Check

Listen to the rendered file from beginning to end, not only to the session that created it. Open it in a player or import it into a clean project without accidentally applying your mix-bus processing again.

• Correct content: check that no track was muted or soloed unintentionally, and that the expected automation and effects are present.
• Clean boundaries: check the first transient, edits, fades and complete ending, including delay and reverb tails.
• Sound and levels: listen for clipping, clicks, excessive sibilance or a low end that masks the rest of the track.
• Playback checks: use your familiar speakers and headphones, then another useful reference such as a car system or small speaker.
• Technical details: confirm the duration, sample rate, bit depth and filename before uploading.

Different systems reveal different things. Small speakers can highlight whether the vocal is clear, but they cannot tell you everything about the deepest bass. Look for recurring problems rather than trying to make every device sound identical.

At a similar perceived listening level, compare your mix with a suitable reference. Do not limit the pre-master simply to match the volume of an already mastered record.^[7]

Communicate With Engineer

A few specific notes help more than a long list of technical settings. Explain what you like about the mix, what concerns you and how the release should feel. Include the intended format and any deadline.

Share Your Vision Clearly

Describe the tone, dynamics and overall character you want to protect. Mention a vocal that must stay natural, a deliberately rough texture, or a bass sound you do not want made thinner. Add timestamps for specific concerns rather than asking for a vague improvement to everything.

Example note: “Please keep the kick punchy and the vocal natural. The top end feels sharp around 2:10. Reference A has the bass balance I like; I am not trying to match its overall loudness. This is version 3, intended for digital release.”

That is an example of a useful brief, not a preset mastering instruction. You do not need to know which EQ, compressor or limiter should be used.

Provide Reference Tracks

Choose a small number of relevant references and explain why each matters. One may illustrate tonal balance while another shows the sense of space or energy you want. Share artist and track names, accessible links and a timestamp where helpful.

References give direction; they do not promise that one recording can be made identical to another. Instrumentation, arrangement and the mix itself still shape the result.

Mastering References

Use references to understand the wider sound, not to chase every peak or copy a frequency curve. Similar genre, instrumentation or energy can make a comparison more useful, but an exact tempo match is not essential.

Turn the louder reference down for a fair comparison rather than pushing your mix harder. Keep the reference outside your own mix-bus processing. Listen for low-end weight, midrange clarity, brightness, depth and the contrast between softer and louder sections.^[7]

Audiolens, mentioned in the original guide, is an optional way to examine a reference’s tonal balance. Playback-simulation tools such as MixChecker are optional cross-checks too. Neither is required to prepare or submit your file, and neither replaces listening to the actual export.

The before-and-after mastering examples on the service page provide another way to hear the sort of changes mastering can make.

Conclusion

A useful pre-master is a finished mix, exported cleanly and accompanied by enough information to understand it. Preserve the sound you have built, check the actual file and make the approved version easy to identify.

Before sending, confirm the mix is complete, the file format and sample rate are correct, the ending is intact, and your references and notes are included. You do not need to make the pre-master as loud as a commercial release first.