Mastering for streaming: loudness, peaks and fair listening tests

Separate three different measurements

• Integrated loudness describes average perceived level across a recording.
• True peak estimates peaks relevant to playback and conversion; it is different from an average level.
• The listener’s playback setting and device affect what is heard. A platform may turn a louder recording down during playback.

What Spotify’s guidance actually says

Spotify describes normal playback normalisation around −14 LUFS, with other listener settings and device exceptions. Its mastering advice discusses headroom and true peaks, including more headroom for louder masters. This is Spotify-specific guidance, not a rule that every distributor rejects music above −14 LUFS or that every service plays identically. Spotify says the normalisation happens during playback. Do not rewrite your entire master on the assumption that one playback number is an acceptance test.

Build a useful listening comparison

• Choose the same musical passage from the mix and the proposed master. Make sure they are genuinely different approved versions.
• Match the perceived listening level for the comparison, using temporary monitoring gain rather than overwriting either original file.
• Compare clarity, bass balance, harshness, vocal position, transients and the relationship between sections. Take breaks and avoid deciding only from the louder option.
• Check headphones and a second familiar listening system at comfortable levels. Note specific issues and timestamps.
• Keep an untouched approved master and document which export is intended for distribution.

An original review example

A band compares a chorus in its mix with the mastered chorus. At unmatched levels the master seems immediately more exciting. After adjusting monitoring gain, they hear that the vocal is clearer but the cymbals are too sharp. Their revision request names that passage and the tonal issue. This produces a more actionable brief than “make it louder”; it does not prescribe one loudness value for every genre.

Check an album as an album

Listen through the running order rather than checking each file in isolation. Consider transitions, intentional quiet passages and overall consistency. A soft introduction does not have to be as loud as a final chorus. Do not remove deliberate dynamics simply to make meters look alike. Retain the final track order, filenames and the agreed listening notes with the release materials.

Avoid unnecessary conversion

Use the approved native-quality source and the format the actual intake requests. Upsampling cannot recreate missing information, and repeated lossy exports can damage the source. The audio delivery checklist explains file inspection separately from mastering decisions. A change to the recording may also raise an identifier question; ask before replacing delivered audio.

Choose help with a clear brief

DistroBolt offers Human Mastering as a separate service. Provide the approved mix and describe the intended sound, references and problems you want addressed. Confirm current price, delivery and revision terms on the service page and written proposal. Mastering does not guarantee playlist placement, a particular playback level on every device or additional income.