In this excerpt from Start to Finish: Dave Kutch - Episode 19 - Mastering Part 3, you’ll hear mastering engineer Dave Kutch state pretty emphatically that he doesn’t aim for specific loudness targets. “It’s the last thing I’m thinking about when I’m mastering,” he says. “It’s been that way since I started, and that’s never changed. It’s [all about] what sounds good.”
He explains that his modus operandi is to make the song sound as good as it can—period. Loudness targets aren’t on his radar. And you know what? He has the cred—and the credits—to take a stance like that. Dave has mastered music for major artists like Billie Eilish, The Weeknd, Dua Lipa, Katy Perry, Alicia Keys, etc.
In the excerpt, Dave gives his take on loudness targets.
On Target
When we discuss loudness targets, we’re talking about the guidelines from the various streaming services, which are largely based on Integrated LUFS (Loudness Units relative to Full Scale, also referred to as LKFS), which measure a song’s average loudness. The services each employ proprietary loudness normalization systems designed to ensure that the perceived loudness is consistent from one song to the next. Without them, it would be challenging for listeners, who would have to keep turning their levels up and down, depending on how loud each song was mastered.
The rise of loudness normalization on Spotify and the other services has had a very positive benefit: it essentially ended the loudness wars. When the loudness wars were raging, mastering engineers were under pressure from artists, producers and record labels to make songs as loud as possible so they would stand out from their competition when played back-to-back. As a result, so much limiting was typically applied to raise loudness that dynamic range was sacrificed, negatively affecting sound quality. Everything was overly pumped up and squashed.
Loudness normalization levels for the major streaming music sites.
But now, if you master at a level that exceeds the loudness target of a particular streaming service, its loudness normalization algorithm will turn down the loudness of your song. Therefore, there’s no longer any reason to make the tradeoff between dynamic range and gain because your song won’t sound any louder when it’s streamed.
It’s better to slightly overshoot the target level than vice versa. The algorithm will turn down if the song is higher than the specified LUFS level. Some services will turn it up if it’s lower, but others won’t. Also, some streaming platforms may use a limiter to bring the level up, and you don’t want any additional dynamics processing applied to your music once it’s past the mastering stage. That’s because it could affect the transients and, therefore, the punchiness of a song.
Peak Loudness
In addition to the LUFS loudness targets, you want to make sure that the True Peak level of your music doesn’t exceed -1dB. This helps avoid inter-modulation distortion when your song is converted from an uncompressed format to one of the CODECs used by the streaming services.
A handy plugin to use when you’re mastering is process.audio Decibel, which will show you all the different forms of LUFS: Integrated, Short-Term and Momentary. It also gives you True Peak levels and TruDyn, a measure of dynamic and lets you open up virtually any other type of audio meter. What’s more, you can calibrate it for different streaming services to see where your mix is compared to their loudness targets.
This layout in process.audio Decibel offers multiple ways to monitor LUFS.
Watching Out
When you’re applying a limiter to your music, remember what Dave said in the excerpt: “Be honest with yourself and know when you’re hearing the difference between your mix being open and breathing, and closed and midrangey and loud, and when you’ve lost transients on your kicks and snares.”
How much dynamic range you need to preserve depends on the type of music. If a song is uptempo or hits hard, or both, you can get away with more limiting. If it’s slower or quieter or acoustic and has big dynamic swings, you need to be extra careful. How aggressively to limit is not just about levels, it’s an artistic decision, as well. Pushing the limiter to higher levels of gain reduction gives you a denser sound, which may work well, depending on the song.
The following examples have been mastered with -14 LUFS integrated as the loudness target. All have the same attack and release settings. The first example you’ll hear has a limiter applying about 2.5dB of gain reduction. According to Decibel, its TruDyn reading is 10.5dB.
The second example is limited more heavily, with an average gain reduction of about 5dB. Its TruDyn reading is 9.1. You can hear it’s a little crunchier sounding than the first one, but for a rock mix like this, it works.
The last one is intentionally squashed too much. The limiter applies between 8 and 9dB of gain reduction, and its TruDyn reading is only 6.9dB. In addition to losing dynamic range and having its transients reduced, it sounds distorted in an unpleasant way.
If you look carefully at this comparison of their waveforms, you can see the difference in dynamic range.
Clockwise from top left: the waveforms for the first, second and third examples.