Concept 2: Measure loudness using a LUFS/LKFS meter.

The different streaming services have different loudness standards and algorithms to take measurements and apply the normalization but for the most part they use the basic unit system of loudness measurement called LUFS or LKFS.

This metering system allows engineers to numerically meter how loud content is and make adjustments to the dynamic range accordingly.

Being able to understand how our music masters are metering with this scale is useful to see what will happen when they are streamed on different services (i.e. will the algorithm gain them up or down to meet the target or not?)

Concept 3: Choose which loudness standard to master to.

Direct your mastering engineer if you are working with one to master to a target loudness level and consult with them about what they feel is an appropriate target level for your music.

If you are mastering jazz or classical music you probably don’t want to make a very loud master for sound quality and dynamic range reasons but if you are making a heavy rock, pop, or, hip hop master that wants to be more intense then a louder target may be more suitable.

iTunes Sound Check and Apple Music/iTunes Radio use a target level of

-16LUFS and this would be a suitable target for more dynamic material.

Tidal uses a target level of -14LUFS that is a nice middle ground for most music that wants to be somewhat dynamic.

YouTube uses a target level of -13LUFS, a tiny bit less dynamic than Tidal.

Spotify uses a loudness target of -11LUFS and as you can see this is 5 dB louder than iTunes/Apple Music.

This is more in the territory of low dynamic range, heavily limited content.

Somewhere in the middle of -16LUFS and -11LUFS might be the best target loudness for your music based on your desired dynamic range but the goal is not to go above the chosen target otherwise your content gets gained down on playback and dynamic range is lost.

In all services except Spotify, content that measures lower than target loudness is not gained up. So for people working with very dynamic classical music or film soundtracks those big dynamic movements will not be lost on most streaming platforms.

However since Spotify is unique and adds gain and peak limiting if your content is below target it is potentially the most destructive sonically.

So should you master to -11LUFS and save your music from Spotify’s peak limiting but lose dynamic range on the other platforms?

It’s a compromise that you have to decide for yourself in consultation with your mastering engineer.

You might want to test out what -11LUFS sounds like in the studio and hear what the effect of that limiting is. Is it better to master that loud yourself and compensate in other ways for the lost punch and lower dynamic range?

Or should you accept that Spotify users get a different dynamic range than iTunes users and let your music be more dynamic for the rest of the platforms?

In all cases there is no benefit to going above -11 LUFS because that is the loudest target level used by any service.

If you go louder than -11LUFS then your music will be turned down and dynamic range and punch will be lost on all the services needlessly and permanently.

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