Apple is addressing the "loudness war" with new mastering specs - what is Spotify doing?


Apple just released detailed specs on how to create the best sounding master for iTunes publishing. When can we expect similar guidelines from Spotify?


They are also addressing the loudness war issue, stating that the "sound check" option in iTunes (similar to the "set same volume" option in Spotify) is an important step to help producers and mastering engineers put an end to the loudness maximation, something most engineers want to do but cannot in the current state of distribution.


The "sound check" feature does not tamper with the audio, it simply lowers the volume on tracks that are mastered with artificial volume boosting. Can we say the same about Spotify's "set same volume" option?


Spotify was early with normalizing loudness in the desktop client which was very positive. To help things even further you should make sure that it is preselected in all new installations and also bring back the feature to the mobile client (why was it removed?). In an ideal world the option is not even selectable but always on, completely removing the need to artificially boost volume in the mastering process.


This may seem like a small technical detail but it is a huge deal for music producers and mastering engineers all around the globe, and in the end it would prove to increase audio quality for all music lovers.

This issue has also been raised in a similar, more popular idea here:

Add your kudos and comments there please! ;)

Volume normalization for mobile devices has been suggested here:

Absolutely cannot fault you for broaching the topic. The loudness wars have done nothing to improve music for consumers, only serving to reduce audio quality -- and, worse, to lower the generally accepted standards.


A couple of comments on your post, though. It sounds like you may know this but your post seems to address distinct topics interchangeably.


(I'm not an expert whatsoever, so this all comes with the disclaimers: "As I understand it..." and "This may not be the correct technical term, but..." )



The iTunes "Sound Check" and Spotify "Set Same Volume" ("SSV" from now on) functions are simply workarounds, and are completely distinct from pursuing an end to loudness wars at the mastering end.


- Sound Check/SSV simply alter the gain on an entire track, either amplifying or reducing all sections and frequencies equally. Essentially the same effect as turning the volume knob up or down so that every track sounds approximately the same average volume, but saving you the effort of doing so. They have no effect on audio quality, per se; only volume.


- The "loudness wars" in mastering have a different origin: signal processing techniques are used to basically push everything further and further toward the maximum amplitude. Loud sections, quiet sections, everything gets made louder, but not equally louder. Quiet sections are amplified more because there's greater headroom between them and the maximum peak level, while loud sections can't be amplified much because they're already at or near peak. The end result that there's less and less difference in volume between the "loud" and "quiet" sections -- i.e. reduced dynamic range.


So I think Apple would be overselling Sound Check by saying it's an important step toward ending the loudness trend. It doesn't address the issue directly -- it can't, really, because it can't artificially create increased fidelity that doesn't exist in the source material. The only thing it can perhaps achieve is to increase people's awareness of the poor audio quality in overly-loud tracks, since you're going to be mildly more perceptive to actual audio quality at lower playback volumes. (Because -- in very simple terms -- your eardrum isn't too busy being shattered instead.)



All that to say: Sound Check/SSV aren't solutions, or even workarounds, really. So whether or not Spotify's SSV option is toggled on by default isn't all that great an issue. (It is toggled on by default, btw -- I've installed the Windows and Mac clients several times in the past few weeks and had to toggled it off each time.)


In fact it's even debatable whether SSV is actually valuable in Spotify, since it works on a per-track basis, not per-album. So an album that's intended to fluctuate drastically in volume during its course.... won't... since Spotify will normalize all the tracks to the same volume individually. (Which is exactly why I toggle SSV off.)



The only way to really rewind the loudness wars is to attack the problem at the source: the master. Which is what it appears Apple is doing. However, iTunes is a primary (if not the primary) digital music outlet, and has a massive enough market share that I can believe Apple can swing their influence in telling people how to master their music. I'm not sure how Spotify obtains their music -- I'm not convinced anyone masters with Spotify in mind, rather that they get "second hand" source material -- so I'm not sure they have quite the same weight to throw around. Though it certainly wouldn't be a bad thing for them to endorse the "anti-loudness" effort.





Casual Listener



Sound Check or SSV will not ever re-induce the dynamics into a loudness-maximized master. While this is theoretically possible using expander processing, it would not be a good idea at all.


What it can do however is to end the loudness war for future record releases. Because as long as maximized audio is played louder for the consumer, the record labels will keep endorsing it, and thus the mastering engineers will keep doing it. While some people may argue that volume maximization is done "artisticly", the truth is that 99.9% of all volume maximization in music mastering is solely to make it louder for the consumer.


That is why Sound Check/SSV is so important. If it is enabled by default, or even forced upon the consumer, the advantage of destructive maximization in mastering will be gone in an instant, and as record labels learn of this, mastering engineers will be directed to stop doing it.


Apple also claims that their Sound Check feature does take albums into consideration, i.e an album is volume-calculated as an album and not as a single track. If SSV works in the same way, I can see no reason why the feature can not be forced upon the customer. Do you?

Casual Listener

I don't believe that "mastered for itunes" was supposed to be a beneficial thing to the loudness war, they don't provide any proof of mastering work, there goal with mastered for itunes is trying to get closer to the trashed CD masters, not getting closer to what high quality is supposed to be. I believe mastered for Itunes is a major money spin. I have tried some mastered for itunes downloads and the dynamic range is as bad as the CDs.


I have created the following idea, providing links to in depth detail about the loudness war and specifying that any special or exclusive mastering job to spotify should be issued with a dynamic range value. I also link directly at the bottom of the post, to another post that will directly help this issue. Created the idea 2 days ago and 5 kudos already.


Rock Star 28
Rock Star 28
Status changed to: Duplicate

This issue has also been raised in a similar, more popular idea here:

Add your kudos and comments there please! ;)

Volume normalization for mobile devices has been suggested here: