Master check before uploading
Before you upload a WAV for your release, have the master checked: Loudness, true peak, clipping, silence, phase and format. Above all, you will see what the platforms will do to the recording when they adjust it to their loudness level.
The master check in Artists Bez Labelu analyses the file right in your browser – it is not uploaded anywhere. The result is for information only and does not block anything; you can send the release even with a red result.
Where to find the check
- In Music releases, under the Master check button at the top.
- Automatically in the recording form when you select a WAV – you will see the result right below the file selection.
- As the Check your master step in the First release guide and in the Campaign planner.
Without logging in, you can also measure loudness and true peak in the online tool LUFS and True Peak check and verify the file format in the tool Audio file check.
What the check measures
| Measurement | What it means | What to look for |
|---|---|---|
| Format | File type, bit depth, sample rate and number of channels | WAV, 16, 24 or 32-bit, 44.1 kHz or higher (no more than 96 kHz for upload, 48 kHz / 24-bit recommended), stereo |
| Loudness (LUFS) | The integrated loudness of the whole recording | You do not have to “hit” any particular value – what matters is what normalisation does with it |
| True peak (dBTP) | The actual peak of the signal, including peaks between samples | No higher than −1 dBTP recommended |
| Clipping | Places where the signal hit the ceiling | Often audible as crackling |
| Silence | Silence at the beginning and end of the recording | No unnecessary silence at the start and no cut-off ending |
| Loudness range (LRA) | How much the loudness changes over the course of the recording | Information about the dynamics |
| Loudest point | Where the loudness peaks in the recording | Helps you find a problem spot |
| Phase correlation | Whether the recording also works in mono | Negative values mean there is a risk that something will disappear in mono |
| DC offset | A shift of the whole signal away from the zero line | Above 1% it is worth fixing – it needlessly eats into the headroom for loudness |
| File metadata | Data written in the file (title, date, software…) | A faulty date (for example a day or month of “00”) is rejected by distribution |
The check also reads the file metadata. If a WAV carries a faulty date (typically a day or month of “00”, as written by Logic Pro X, for example), the recording form rejects the file. Just click Remove metadata from the selected file directly in the form, or download the WAV without metadata in the Master check – the sound does not change in any way. The online tool WAV metadata cleaner can do the same.
What the platforms will do to the recording
Platforms adjust the loudness of recordings to their own target – this is called normalisation. That is why the check does not just look at your master’s numbers, but also at how the recording will sound after normalisation. You will find the details in the article LUFS and True Peak across platforms.
| Platform | Target loudness |
|---|---|
| Spotify, YouTube, Amazon Music, Tidal, SoundCloud | around −14 LUFS |
| Deezer | −15 LUFS |
| Apple Music | −16 LUFS |
The platform turns a louder master down
And the true peak drops as a result. Spotify turns a master at −12.5 LUFS with a true peak of −0.2 dBTP down by 1.5 dB, and the true peak will be −1.7 dBTP. That is fine.
The platform may turn a quieter master up
And the true peak rises as a result. If it went above 0 dBTP after being turned up, there would be a risk of distortion.
In the Evaluate for switch, you choose the platform. The before-and-after normalisation chart and the map of safe zones show where your master stands. That is why the check does not report a loud master that the platform simply turns down as an error.
What to do with the result
If something is red, consult your mastering engineer. The recommended true peak limit is −1 dBTP – it ensures that conversion to the platforms’ formats does not distort the recording.
How to approach loudness when mastering is explained in the article What LUFS and True Peak to aim for in digital distribution.
Frequently asked questions
Will my file be uploaded anywhere?
No. The analysis runs in your browser and the file does not leave your computer until you upload it to a recording yourself.
Do I have to adjust my master if it is louder than −14 LUFS?
No. The platform simply turns it down during playback. Keep an eye mainly on the true peak and clipping.
The check reports clipping, but I cannot hear anything.
Brief clipping may not be audible in your player, but it can show up after conversion to the platform’s format. Listen to the reported spot and consult your mastering engineer.