Master QC Checklist: What to Check Before You Deliver
Published · by Loopin
Run these eight checks on every master before you send it, whoever or whatever made it. It takes ten minutes and catches the problems clients email about.
Check 1–2: level and peaks
1. Loudness. Read integrated loudness against the target you promised. About −14 LUFS is the usual streaming reference; punchy genres often sit louder, and a reference like Loopin’s Punchy feel is about −11. Our LUFS guide explains the numbers.
2. True peak. Keep it at −1 dBTP or lower so conversion to lossy formats does not clip. Listen to the loudest bar for crackle, not just the meter.
Write the numbers on a card next to your monitor: target LUFS, ceiling, format. A checklist you have to look up is a checklist you skip on a busy day.
Check 3–4: tone against the reference
3. Level-matched A/B against the mix. Match loudness before judging; a louder version always sounds better for a few seconds. If the master loses punch or vocal clarity, the cause is usually over-limiting.
4. Tone against a reference. Play one commercial track at matched loudness. Compare low end, vocal presence and top end, not volume. Fix what is wrong in the mix, not by stacking more processing.
Take two passes: a loud listen at normal volume and a quiet one at about half. Problems with vocal level and bass balance show up most at low volume.
Check 5–6: stereo and mono
5. Mono sum. Fold to mono for 30 seconds. Bass and lead vocal should stay put; if the hook disappears, the stereo effects are fighting each other.
6. Phone and car. Play it once on a phone speaker and once on earbuds. A master that works only on studio headphones is not finished. See the car test for masters.
If a mono check reveals a problem, the fix lives in the mix. Wide effects on bass and kick are the usual cause; narrowing them often saves the hook.
Check 7: defects, start to end
7. Listen to the whole file. Not just the chorus. Check the first second, the end fade and every transition for clicks, clipped transients and abrupt silence. Ten minutes of attention here is the difference between a pro delivery and a revision.
If you find distortion that was not in the mix, back off the loudness target and re-run. If it was in the mix, tell the client the mix needs a fix. Automatic mastering cannot repair it.
Keep a short notes file for each client: what you fixed, what you flagged, what you were told. Next time they send a track you already know their taste.
Check 8: the files
8. Format and names. Right format, right sample rate, filenames that sort in track order, and no leftover versions in the folder. Loopin exports a 16-bit WAV, so if the client needs 24-bit, say so before you start, not after.
Final step: run it through the free masterer if you need a reference master to compare against, and keep the clean versions archived. Our mastering checklist covers the full release flow.
Paste the eight checks into your notes app and tick them off per track. Level, peak, tone, mono, phone, defects, files, notes. That is the whole list.
Copy the checklist into your notes
Paste this and tick it per track: 1 loudness on target, 2 true peak at −1 dBTP or lower, 3 matched A/B against the mix, 4 reference check, 5 mono sum, 6 phone and earbuds, 7 full listen start to end, 8 format and filenames.
Run it on automatic masters, your own masters and anything a client sends back as “final”. A checklist that treats every file the same catches the mistake you were sure you did not make. If one check fails twice on the same client, put it in your intake notes so the mix arrives fixed. Need a first-pass reference to run the checklist against? Master the track free and check it like any other file.
Frequently asked questions
What should I check before delivering a master?
Level (LUFS), true peak under -1 dBTP, tone against a reference, mono sum, phone and car playback, start-to-end defects and file naming.
What true peak should a master have?
At or below -1 dBTP is a safe ceiling for streaming and lossy conversion.
What LUFS should a master be?
About -14 LUFS is the common streaming reference. Louder genres sit higher, so confirm the client's target before delivery.
How long does a QC pass take?
About ten minutes per track once you have a routine, plus extra time to listen on a second system.
Do automatic masters need a QC check?
Yes. Every master does. Automatic mastering is a fast first pass and cannot fix a bad mix, so check it the same way.