Audio file requirements
The exact audio specs Run accepts, the warnings that do not stop a release, and how to export a master that clears the checks first time.
Upload one lossless stereo master per track: WAV at 16, 24 or 32-bit, or 16-bit FLAC. The sample rate must be 44.1 kHz to 192 kHz, and each file can be up to 2 GB.
Use The specs to check whether a file is accepted. The warnings lists findings that go to a reviewer without stopping the release on their own.
The specs
| Requirement | What Run accepts |
|---|---|
| Format | WAV or FLAC only |
| WAV bit depth | 16, 24 or 32-bit, including 32-bit float |
| FLAC bit depth | 16-bit only. Deliver WAV for anything deeper |
| Sample rate | 44.1 kHz minimum, 192 kHz maximum |
| Channels | Stereo, meaning exactly two channels |
| Length | At least 1 second |
| File size | Up to 2 GB per track |
| Container | A real WAV or FLAC file. A FLAC stream wrapped in another container is not accepted |
Lossy files are refused outright. MP3, AAC, M4A, OGG and Opus are not masters. AIFF is not accepted either, even though it is lossless: if your session bounces to AIFF, convert it to WAV before uploading.
The wizard’s file picker only offers WAV and FLAC, so a lossy file rarely gets that far. The checks are there for the file that claims to be one thing and is another.
The warnings
None of these stop your release. They are worth fixing anyway, because each one is something a listener or a store will notice.
| Warning | What it means |
|---|---|
| True peak above -1 dBTP | The master has under 1 dB of headroom. Store transcodes can clip it |
| Loudness above -9 LUFS | Stores normalise to around -14 LUFS, so a master this hot is turned down a long way and mostly loses its dynamics for nothing |
| More than 2 seconds of silence at the start or end | Usually an export that was not trimmed. Deliberate silence is fine, and the reviewer can see the difference |
| Both channels identical | A mono recording sitting in a stereo file. Fine if the recording really is mono |
| The spectrum stops around 16 kHz | The master probably came from a lossy file |
How to export correctly
- Export from your session, not from a file you downloaded or bounced for reference. The chain should be session to master to Run, with no lossy step anywhere in it.
- Choose WAV. 24-bit is a good default; 16-bit is fine. Use FLAC only at 16-bit.
- Keep the session’s own sample rate as long as it is 44.1 kHz or higher. Upsampling a 44.1 kHz mix to 96 kHz adds nothing.
- Export stereo, even for a mono recording. The file has to have two channels.
- Leave headroom. Set the limiter ceiling around -1 dBTP rather than 0.
- Do not chase loudness. Every store normalises, so a master at a sane loudness arrives sounding the way you mixed it.
- Trim silence at the head and tail, unless it is part of the track.
- Check the length. A file shorter than a second is treated as an error, not a track.
Uploading
- Open Tracks in your release.
- Drop your masters into the section to create tracks, or open an existing track and add its file.
- Check the resulting titles and order while the files upload. Uploads continue in the background and can resume after a connection drops.
A track with no audio file attached cannot be submitted. If a master fails the checks after submission, reopen the release, replace that one file and submit again: see editing and resubmitting.
What is checked, and what is not
The checks read the file itself: format, bit depth, sample rate, channels, length, size, levels and the shape of the spectrum. They do not judge the mix, the arrangement or the performance.
Separately, every track is run through content matching against a catalog of existing recordings, which is about rights rather than audio quality. A match does not fail your release on its own, but it goes to a person, and covers, remixes and samples need their clearance documents on file. See covers, remixes and samples and what review checks.