Skip to main content

14 Oct 2013
FOR IMMEDIATE RELEASE October 15, 2013

THE LAST BATTLE OF THE LOUDNESS WAR HAS BEEN WON
Orlando, Florida: “The debilitating loudness war has finally been won,” said mastering engineer Bob Katz on the eve of the Audio Engineering Society (AES) Convention in New York City. The last battle will be over by mid-2014.”

“I have just completed loudness measurements of iTunes Radio using iTunes version 11.1.1. Tunes Radio’s audio levels are fully-regulated, using Apple’s Sound Check™ algorithm. This is a very important development,” Katz said.

During several hours’ testing, Katz measured the output level of several stations, and concluded that each song’s loudness averages -16.5 LUFS, within better than 2 dB, usually plus or minus 1.5 dB. The Apple release notes state that version 11.1.1 “improves stability”, which he interprets as having solved some loudness regulation issues which were present in the previous iTunes release.

It is clear that music producers want their music to sound as good as possible on the nascent but already popular iTunes Radio platform, given the many listeners instantly available. This immediately opens an opportunity to curtail the loudness race within the next few months. Added Katz, “The way to turn the loudness race around right now, is for every producer and mastering engineer to ask their clients if they have heard iTunes Radio. When they respond in the affirmative, the engineer/producer tells them they need to turn down the level of their song(s) to the standard level or iTunes Radio will do it for them—and not always in a pleasing way. iTunes radio will not just ‘turn down the volume,’ but may peak-limit the important transient peaks of the material and make the song sound ‘smaller’ and less clear than its competition.”

Katz suggests, “The engineer/producer should also tell their clients to turn on Sound Check in iTunes to hear their music exactly the way they will be broadcast on iTunes Radio. This makes all music played in iTunes, whether it be on IOS devices played while jogging, connected in the car, or on the desktop computer, perform consistently. It’s a revolution in the making, with instant positive results.“

Katz’s discoveries show that current squashed and smashed pop releases are being attenuated more than 7 dB in order to make their loudness equal to that of more-conservatively mastered releases. In other words, true peak levels of current pop songs are as low as -7.8 dB below full scale! “There is so much available peak headroom now in iTunes Radio that anyone who wants to master their songs with more conservative levels and prefers higher peak-to-loudness ratios will produce music with immediate loudness and sound quality advantages, compared to what’s being played out there now. The cream will soon rise to the top. The music will sound better, even a bit louder, and will attract more listeners. iTunes Radio is already so popular that it will end the loudness race by force majeure. This development is a great opportunity for producers to explain and demonstrate to their clients how to make their songs sound better on iTunes Radio and everywhere else.”

Sound Check is on by default in iTunes Radio and cannot be turned off. However, currently, song files which are on the computer or the iDevice are not loudness-regulated by default, so consumers and musicians who listen to iTunes Radio will quickly discover that Radio sounds more consistent than their playlists, that they don’t have to turn their volume controls up and down when listening to Radio. iTunes Radio also reveals that overcompressed songs sound worse, and not louder than their competition. Therefore, it is imperative for producers and engineers to educate clients to turn on Sound Check so they can hear what their songs will sound like on Radio, and for better listening. “Magazines, newspapers and other media outlets should encourage their readers to turn on Sound Check to make their devices conform with iTunes Radio,” said Katz. “All it takes is a little educating and self-discovery.”

“There will be still some skirmishes, but the main battle has just been won. Producers, engineers and musicians will ultimately discover this news themselves, but journalists and producers can hasten the close of the war, starting right now.” To discuss this important event, Katz invites musicians, producers and engineers to join the free discussion forum at http://www.digido.com.

The discovery that iTunes Radio may be regulated with the Sound Check algorithm was made by engineer Robin Reumers of Galaxy Studios, Belgium, on September 20th. Reumers then began a discussion with fellow loudness researchers Thomas Lund of TC Electronic and Bob Katz of Digital Domain Mastering. Katz immediately made measurements and found some iTunes Radio Stations that were inconsistently regulated, and he suggested that iTunes Radio might not conform to Sound Check. However, the maintenance release of iTunes opened up a possibility, and on October 15th, Katz tested iTunes 11.1.1 and confirmed that Apple appears to have conquered the loudness inconsistencies. Reumers pointed out that this must mean that Sound Check metADATa is being broadcast on iTunes Radio and that Apple had to tweak the receivers in order to properly react to the metADATa. Apple does not normally comment on their technical data or procedures, leaving the task of confirming measurements to the audio community.

“I urge readers of this press release to enter into discussion on the forum at http://www.digido.com,” said Katz. “Especially if you have any information on Apple’s technical practices. The forum will serve as a central meeting place for producers and engineers who want to see the loudness war end as quickly as possible.”
Contact: Todd Hays or Mary Kent, tel. 407.831.0233 or write ofcmgr@digido.com

Topic Tags

Comments

bouldersound Sun, 10/20/2013 - 18:12

audiokid, post: 407882 wrote: “The way to turn the loudness race around right now, is for every producer and mastering engineer to ask their clients if they have heard iTunes Radio. When they respond in the affirmative, the engineer/producer tells them they need to turn down the level of their song(s) to the standard level or iTunes Radio will do it for them—and not always in a pleasing way. iTunes radio will not just ‘turn down the volume,’ but may peak-limit the important transient peaks of the material and make the song sound ‘smaller’ and less clear than its competition.”

Evidently Mr. Katz forgot that it's the songs with lower RMS values and more dynamics that will be limited, not the ones that are already limited to death. The loud songs can simply be attenuated to the desired target value.

Not only is the statement wrong, it assumes that iTunes Radio is the whole world of streaming. I stream audio all the time and this is the first I've heard of iTunes Radio. But then I don't buy Apple products or use iTunes since I'm quite capable of making my own decisions about which audio files I should be allowed to burn to disc etc.

MrEase Mon, 10/21/2013 - 04:49

bouldersound, post: 407887 wrote: Evidently Mr. Katz forgot that it's the songs with lower RMS values and more dynamics that will be limited, not the ones that are already limited to death. The loud songs can simply be attenuated to the desired target value.

I'm not at all sure that Katz got it wrong and think it more likely that you have. Surely with the target of -16.5 LUFS , there is now room for the dynamic peaks in "better" mastered content. I can only see that your argument would stand up if the attenuation was set by just the peaks of any content and not the LUFS level.

This seems to be backed up by the arguments in the text that the target is to get all content played on the itunes radio to have similar loudness and hence it will be the horribly flattened "pop" content that will be attenuated (as you suggested yourself) but will not be taking any advantage of the available dynamic headroom available.

audiokid Mon, 10/21/2013 - 08:59

I don't know all the details either but to add, I've heard rumors and listened to Bob talking about this for a while now. Audio that has a "flat top" will actually be penalized and lowered in volume. I'm guessing its a simple calculation based on the obvious transient level and number of transient peaks that don't exists for the norm.

The more natural transients, the better the rating or score. thumb

The flat line crap is actually going to be pushed down and its about time! How cool would that be?

audiokid Mon, 10/21/2013 - 09:18

Thinking out loud here, I know electronic music is already transient compromised. Rich acoustic information vs VSTi generated, big difference here. I wonder how they will get around this? Through categories. Through an automated sampling process?
Talk about a new way to fool or rework the system once again. But, I do know first hand when I run electronic music through my hybrid system, I add transients on purpose.

This is another reason why so many uniformed people are talking about "glue". Trying to "glue" electronic/ digital music to vocals is a trick indeed. I've been playing with this for 25 years now. Acoustic music and VSTi mixed together is a bitch to get right. So, every kid on the block is buying into the " better get an API 2500" or SSL G comp" to glue your mix. Its all a bunch of hype and BS to me but it works because it forms a common distortion to the entire wave. Processing stems and distorting them in various ways (colours) helps the wide transient pallet between real and digital fit better.

I'm liking where this is going!
Interesting times for Mastering Engineers and hybrid processing .

MrEase Mon, 10/21/2013 - 10:20

audiokid, post: 407905 wrote: Thinking out loud here, I know electronic music is already transient compromised. Rich acoustic information vs VSTi generated, big difference here. I wonder how they will get around this? Through categories. Through an automated sampling process?
Talk about a new way to fool or rework the system once again. But, I do know first hand when I run electronic music through my hybrid system, I add transients on purpose.

I don't think the genre is going to be relevant to where this is (hopefully) going. My take on all this agrees with Bob's points and I think that the quote "Boulder" picked is where he perhaps misinterpreted things.

To explain my thoughts on the article...

Apple are, by their own stated standard, going to ensure that all streamed tracks will have a similar perceived loudness and that will equate to -16.5 LUFS. Any tracks that already meet this requirement and whose peaks do not exceed 0dBFS will not need any further processing by them.

If a typical overcompressed modern track is played, it will automatically be attenuated to meet the -16.5 LUFS standard (but naturally will have no transients). If a track with a large dynamic range is encountered, such that it is less than -16.5 LUFS, then it will be amplified. However in this case the peaks that will now exceed 0 dBFS will be (apparently not too elegantly) limited.

Clearly the target for mastering for Apple airtime will be to master tracks to meet the required standard and can therefore take full advantage of the headroom provided for transients. I think the point Bob is making is that this will have an impact on those producers who currently insist on maximising percieved volume to the limit and crushing every single transient in the loudness war. They will now have absolutely no benefit in doing so. Hurrah!

bouldersound Mon, 10/21/2013 - 10:49

MrEase, post: 407899 wrote: I'm not at all sure that Katz got it wrong and think it more likely that you have.

Based purely on reputation I would agree with you, but I'm basing this on the information given, not reputations.

MrEase, post: 407899 wrote: Surely with the target of -16.5 LUFS , there is now room for the dynamic peaks in "better" mastered content. I can only see that your argument would stand up if the attenuation was set by just the peaks of any content and not the LUFS level.

This seems to be backed up by the arguments in the text that the target is to get all content played on the itunes radio to have similar loudness and hence it will be the horribly flattened "pop" content that will be attenuated (as you suggested yourself) but will not be taking any advantage of the available dynamic headroom available.

Bob Katz wrote: iTunes radio will not just ‘turn down the volume,’ but may peak-limit the important transient peaks of the material

This is incorrect. Loud songs will be turned down with no limiting needed. Quiet songs may be turned up, and if they have to be turned up more than the available headroom they will have to be limited. There's no logical reason to attenuate and limit any song.

The disadvantage to mastering loud isn't that the dynamics your audio will be changed by Sound Check, it's that the track won't be louder than the next guy anymore, just more compressed (because that's how you mastered it).

Here's a quote from the Apple.com page explaining Sound Check confirming that boosting/limiting may be applied (in stunningly bad English):

http://support.appl… wrote: 2. Any boosts in playback volume are designed to be protected against clipping by iTunes' build-in limiter.

MrEase Tue, 10/22/2013 - 04:45

bouldersound, post: 407911 wrote:
This is incorrect. Loud songs will be turned down with no limiting needed. Quiet songs may be turned up, and if they have to be turned up more than the available headroom they will have to be limited. There's no logical reason to attenuate and limit any song.

The disadvantage to mastering loud isn't that the dynamics your audio will be changed by Sound Check, it's that the track won't be louder than the next guy anymore, just more compressed (because that's how you mastered it).

I think that's pretty much what I was saying in my last post??? Of course if attenuation is applied, limiting is irrelevant but, as per my earlier comment, anything that is lower than -16.5 LUFS will be amplified and hence peaks will be limited.

I think that the how's and why's of processing that will be applied by soundcheck to pre-existing tracks is not really the argument put forward by Bob. It's really about the future.

That's why I think we seem to disagree. I'm not concerned about what happens to any track currently available but am thinking about what an ME will do in the future when mastering for Apple Radio.

I think Bob is saying is that any content that meets the soundcheck requirements will not incur any further processing. Therefore, in the future, to mix/master for Apple Radio, the ME should be aiming to ensure his content does not receive any (usually unwanted) post processing from the soundcheck algorithm. If this is done, it is not in the interest of the ME to compress anything to the point that is regularly done with other media. Any decent ME should therefore be taking full advantage of the transient headroom that inevitably becomes available - by the Apple definition. Pressure from any producers or musicians to make their tracks sound louder - or at least as loud as other "competing" tracks becomes absolutely irrelevant as the loudness is now defined by Apple Radio.

In a nutshell, mastering for Apple Radio clearly defines the targets and in doing so enables the ME to include transient peaks without upsetting anyone. Surely this is a good step in the battle against the loudness wars?

bouldersound Tue, 10/22/2013 - 09:10

MrEase, post: 407929 wrote: I think that's pretty much what I was saying in my last post???

Yes, I agree with your last post, which you posted while I was writing my response to:

MrEase, post: 407899 wrote: I'm not at all sure that Katz got it wrong and think it more likely that you have.

So now we both agree to disagree with that one point Katz made:

Bob Katz wrote: ...they need to turn down the level of their song(s) to the standard level or iTunes Radio will do it for them—and not always in a pleasing way. iTunes radio will not just ‘turn down the volume,’ but may peak-limit the important transient peaks of the material and make the song sound ‘smaller’ and less clear than its competition.

MrEase Tue, 10/22/2013 - 09:53

bouldersound, post: 407933 wrote: So now we both agree to disagree with that one point Katz made:

Originally Posted by Bob Katz
...they need to turn down the level of their song(s) to the standard level or iTunes Radio will do it for them—and not always in a pleasing way. iTunes radio will not just ‘turn down the volume,’ but may peak-limit the important transient peaks of the material and make the song sound ‘smaller’ and less clear than its competition.

I guess that depends on how you read Bob's English! :confused:

While he mentions both "turning down the volume" and peak limiting in the same sentence, I personally did not read them as occuring concurrently which seems to be your assumption. I think even Bob would not expect both to happen in one pass! That's why I seperated the two cases thinking you had not appreciated the volume up AND volume down requirements.

Now I don't know whether I'm right or wrong in the way I read it as I see it just as an ambiguity in the English. That doesn't bother me so long as the understanding is now clear for everyone. Is it?

bouldersound Tue, 10/22/2013 - 10:47

I think we all understand the principle, that loud songs will be turned down and quiet songs will be turned up and likely limited. Bob's comment seems unambiguous enough to me, that loud masters will be turned down and might also be limited. I think he was just eager to make the point, that mastering loud is going to be a clear disadvantage, and overstated the case a little.