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by cthalupa 2352 days ago
The Loudness War is, thankfully, starting to taper off - largely because of YouTube ( https://productionadvice.co.uk/youtube-loudness/ ) and Spotify ( https://artists.spotify.com/faq/mastering-and-loudness#what-... )

Since YT and Spotify are some of the predominant ways people listen to music these days, and they normalize loudness, music producers are starting to go back to more normal masters, thankfully.

7 comments

I've always been curious about Spotify's approach on this, because truth be told the service on good quality speakers does sound rather good.

I'm very pleased by everything I just read in this link — they really think of the user first, and favor music quality and the general experience. It's exactly how I did/do it myself, manually.

Awesome, really awesome to learn that the loudness war is finally coming to a close.

I don't know how normalization is done, but I do know that Spotify are very professional when it comes to audio quality. They do double-blind testing with setups by audio engineers to evaluate end-to-end quality when evaluating changes.
The double-blind scientific approach to audio testing ("ABX") has long been a major point of contention between "objectivists" and "subjectivists"[1]. This has been a godsend for the marketing marketing of some snake-oil companies in audiophile circles.

Really glad to know Spotify is on the side of science, here.

[1]: This blog has got to be the most interesting I ever read on whatever topic it touches, including the objective vs subjective debate: http://nwavguy.blogspot.com/2011/05/subjective-vs-objective-...

Do you mean double-blind testing benefits snake-oil companies? If so, may you expound on that? To my understanding, double-blind tests are meant to avoid un/conscious bias during testing.
No, on the contrary! Sorry for my ambiguous writing. Indeed double-blind is the only way to go.

What I meant is that there is a sizeable chunk of the audiophile industry (a certain press, electronics brands, stores and even studios themselves) that conveniently avoids any and all scientific testing, and promotes typical snake-oil "features" and "specs". Quite sadly for their abused customers.

One of the worst trends in my opinion was faking technical format quality by using different masters on each — with the shitty master on CD/MP3 and the good one, more dynamic, on DVD/SACD/vinyl etc. The latter always sounded better simply because it wasn't the same source!

In such matters, I guess we can trust Spotify based on their claims, and anecdotally I tend to believe them.

I assume they set a target of, say, -14 LUFS (Loudness Units Full Scale), take a reading of the integrated value for the whole track, and then turn the volume of the whole track down by whatever dB value will hit the target.

This avoids the problem of cruder methods, where you take, say, the peak dB as the "loudness" of the track. Doing it that way would take a fairly quiet song with one overly dramatic drum hit and make it so you couldn't hear the rest.

EDIT: I think they will also turn a track up if it's under the target, but I'm not absolutely sure. There would be no real reason not to.

I think they mentioned ReplayGain with AAC and ogg formats, but it's possible they use some custom implementation. There's a good deal of information[1]; it is indeed not peak normalization:

> ReplayGain is different from peak normalization. Peak normalization merely ensures that the peak amplitude reaches a certain level. This does not ensure equal loudness. The ReplayGain technique measures the effective power of the waveform (i.e. the RMS power after applying an "equal loudness contour"), and then adjusts the amplitude of the waveform accordingly. The result is that Replay Gained waveforms are usually more uniformly amplified than peak-normalized waveforms.

Generally we indeed target both up or down in loudness (although 'up' is quite rare, typically high-end recordings of classical or jazz or otherwise very dynamic pieces).

Honestly, everything I read screams that Spotify really hired the right people to make these decisions.

Now I only have to rent about their handling (or rather, lackthereof) of metadata — how hard is it to display an actual first release date? but meh. Audio quality is great, no question about it. I just wish they'd stream FLAC in very-high quality + "quiet" environment settings (the "pure hi-fi" experience so to speak), but that'll come in due time I suppose.

[1]: https://wiki.hydrogenaud.io/index.php?title=ReplayGain

YouTube's volume normalization seems to only reduce the volume of overly loud video, but doesn't add gain to videos that are too quiet.

I guess they don't want to bother with limiters, so understandable.

Musicians and engineers don't want their work 'modified' by the streaming service to make it louder.
I was hopeful when I heard about mainstream loudness normalisation. I've been using ReplayGain for years and it's still superior due to storing both track and album level. It's unclear to me what Spotify etc is doing, but it's is track normalisation it's going to ruin albums.

There's a bigger problem, though. My girlfriend complained about volume fluctuations in her car between tracks. She uses an iPhone so I enabled "Soundcheck" (Apple's normalisation). It works fine in the car. But now she complains that headphones simply aren't loud enough. It turns out that the volume controls are essentially made for overly-compressed, loud content and can't sufficiently amplify dynamic content.

So, unfortunately, people will just turn it off and there's still an advantage to mastering "loud".

In my experience, noise-cancelling headphones have made a big difference. The music doesn't need to compete anymore and you can lower the volume and enjoy the dynamic range.

I also wonder if the resurgence of vinyl, and rise of home producers on bandcamp/soundcloud/etc have helped contribute.

Noise cancelling headphones and ear plugs have been a god send. I just recently got the new AirPods and the noise cancelling in those is phenomenal, I've only experienced better in bulky over ear headphones. If you're in the market for noise cancelling ear plugs, I can definitely recommend them. The mic doesn't seem very good though, getting a lot of complaints about low volume. Oh well, can't have it all!
Does this discourage folks from applying excessive dynamic range compression? Compressed tracks still sound louder.
With normalization, a track with excessive compression and a normally mastered track will have the same loudness. The compressed one will simply have less dynamic range.
It reduces the appeal, but compressed tracks will still sound louder. It depends how advanced the normalisation is. The ideal situation would be something like Dolby's dialogue normalisation where the level is determined from a specific part of the soundtrack rather than the entire thing. It's not obvious how this would work with music, though.
The volume normalisation on Spotify is optional. I can't remember if it's on or not by default.
From what I recall, it's on and set to 'medium' by default. It's become somewhat of a habit to set it to 'quiet' any time Spotify shows me a release announcement (which tells me the settings got reset to default)
that link does not show at all how spotify's policy counters loudness wars. it actually says that they apply a limiter the same as you would to get a loud master. so essentially if a musician avoids the loudness war, spotify applies its principles no matter what
I think you're misunderstanding what the issue is with the loudness war. The problem isn't making a loud master - it's that the dynamics are crushed and the audio signal clips.

Spotify normalizes volume to a LUFS level, which is not nearly the same thing as overly compressing dynamics and causing clipping.

https://www.sweetwater.com/insync/what-is-lufs-and-why-shoul...

AFAIK they simply mess up your mastering if you don't comply.