5 Comments

Every time I talk with my friend John Kellogg, I learn something new. John’s the vice president of Advanced Strategic Solutions for Xperi, parent company of DTS. That basically means he’s a liaison between Xperi and the music and movie production communities, a position he previously held for Dolby. John spends a lot of time in recording studios, and has a very good one of his own, too, so he’s always up on the latest trends in pro audio. Thus, when he recently told me, “Oh, the loudness war’s over; it’s all LUFS now,” I had yet another of the “Wait . . . what?” moments common to our conversations.

As John explained, the shift toward streaming music platforms and away from CD has increasingly made streaming services the gatekeepers between music producers and music listeners—a role formerly held by CD mastering and production services, and still held, to some degree, by radio stations. Once an artist or record company hands their digital music files to a streaming service, the streaming service then decides how best to present them.

John KellogJohn Kellogg

Except perhaps for niche services catering to audiophiles, music streaming services strive to keep a broad spectrum of customers happy. One way they can do this is by adjusting the volume of individual music files so that playback level remains fairly consistent from tune to tune and album to album, so listeners don’t need to adjust the volume—something that’s especially important for curated playlists featuring multiple artists. Typically, this feature can be defeated—for example, Amazon Music HD and Spotify have an option to turn volume normalization on and off—but the apps usually have volume normalization on as a default.

To implement volume normalization, one measures the average level of a music file, then adjusts the volume for that file so its average volume matches a certain target, such as -15dBFS (i.e., 15 decibels below the maximum possible signal level, or full scale). Volume normalization has typically been done using RMS average level measurements spanning the full audible spectrum. More recently, volume normalization has been done using LUFS measurements, which were standardized in 2011. LUFS stands for “loudness units relative to full scale,” and it’s designed to reflect the fact that humans don’t sense all frequencies of sound equally—a theory embodied in the equal loudness contours, better known as the Fletcher-Munson curves.

LUFS incorporates K-weighting, which combines two filters. One filter compensates for the acoustical effects of the human head; it’s a shelving-type treble-boost filter that starts kicking in at 500Hz and levels off at +4dB above 4kHz. The other is a high-pass (bass roll-off) filter with a -3dB point at 60Hz and a slope of roughly -10dB/octave. By measuring average level with these filters in place, LUFS provides a more accurate assessment of how a human will perceive the average volume than a simple broad-band RMS or peak-level measurement can.

A LUFS value reflects the difference between full-scale (or 0dBFS) and the average weighted loudness. So a LUFS value of -15 is 15dB below full-scale, after the weighting filters are applied.

Back in the days when CD changers, early digital music file players, and radio stations served up our music, record producers and mastering engineers couldn’t be sure how loud the tunes preceding and following theirs on a playlist or radio program would be. But they all wanted their recordings to sound at least as good as everybody else’s—and as anyone who’s conducted controlled listening tests knows, the human ear tends to perceive a louder music source as sounding better. This resulted in the “loudness war” of the last 20 years or so, where mastering engineers (often at the insistence of record companies) would heavily compress a recording’s dynamic range so its average level might be just a few dB below full-scale. Thus, a tune would have an average loudness at least as loud as the previous or next tune—but its dynamic range would be so compressed that the impact of loud transients (encountered in drum hits, bass-guitar slaps, etc.) was lost and the music sounded much less lively and realistic.

LUFS targets for streaming services are typically somewhere in the mid-teens: for example, Amazon is -11, Apple Music is -16, and Spotify is -14. If a file mastered in the peak of the loudness war era for an average level of, say, -5dB RMS, is played through these streaming services with the volume normalization on, the service will bring the volume down to its LUFS standard. The file won’t sound any louder than any other, but it will still suffer the sonic degradation of extreme dynamic-range compression, and its peak loudness will actually be lower than that of a less-compressed file.

Knowing that their files will be played back with the same reasonable average loudness as everyone else’s gives recording and mastering engineers the freedom to incorporate more dynamic range into their productions. They may still want to master with higher LUFS values for CDs, which will necessitate more extreme dynamic-range compression. But considering that the CD is no longer the primary focus for most of the music industry, the record company may not wish to pay the additional mastering costs—and the CD will sound better at the streaming-friendly LUFS value. It’s quite an ironic twist that the popularity of streaming services may end up making CDs sound better, isn’t it?

Reaper Waves

To see the difference among typical LUFS values, I ran a recording through the Waves WLM Plus Loudness Meter plug-in, which is used with Reaper digital audio workstation software, and adjusted the level and dynamic range compression to hit -14 LUFS (the Spotify target) and -6 LUFS (a value that might have been common in the heyday of the loudness war). The recording I chose was “Aprender,” a tune I recorded with saxophonist Ron Cyger for our upcoming album. The reason I chose this one wasn’t purely for shameless self-promotion; it was also because I needed an unprocessed mix that I knew hadn’t gone through dynamic-range compression.

The graphs here show the waveform for the first two minutes of “Aprender” at different LUFS values. The original, uncompressed mix (top graph) had a measured average loudness of -19 LUFS. I then applied a light 4:1 compression ratio so the signal peaks wouldn’t clip (i.e., exceed 0dBFS) and raised the level by 5dB, which gave me a Spotify-optimized average loudness of -14 LUFS (middle graph). Finally, I applied a heavier compression ratio of 9:1 and raised the compressor threshold to achieve average loudness of -6 LUFS (bottom graph), which is more typical of what we’d hear from loudness war-era masters.

Graphs

You can see how the -14 LUFS version still has a good amount of dynamic range. In fact, the compression I used for that version is comparable to what I use for most of my music productions, and it’s similar to what I used for the soundtrack of the YouTube video in the link above. But the -6 LUFS version has very little dynamic range. I listened to it only briefly, but from a dynamic standpoint, it sounded something like what you hear when you play music from an AM radio station through a high-quality stereo system. Of course, what you see here represents just a quick attempt by someone with limited mastering experience to hit certain LUFS values. A professional mastering engineer would know the right tricks and tools to get better sound at -6 LUFS—but still, it’s probably not going to sound great.

I guess you can sum all this up by saying that the loudness war is over, and audiophiles won!

. . . Brent Butterworth
This email address is being protected from spambots. You need JavaScript enabled to view it.

Say something here...
Log in with ( Sign Up ? )
or post as a guest
People in conversation:
Loading comment... The comment will be refreshed after 00:00.
  • This commment is unpublished.
    sS · 1 months ago
    STREAMING PLATFORMS DON'T GIVE A SHIT ABOUT LOUDNESS WAR.

    The current streaming platforms turn down the volume to about -16 or -14 for a matter of audio comfort regarding the user. They lower the general volume so there are no variations between songs, turning it less annoying for the user. Audio platforms don't care about the Loudness war. They may not even understand that concept.

    Loudness war was brought by technology (it had to happen), but this "war" never ends. There will always be producers or artists who seek to sound as loud as possible. Only the knowledge and good practices of the producers will make it "disappear" in the future.

    A more realistic approach for streaming services would be around -8 to -12.
    • This commment is unpublished.
      Brent Butterworth · 1 months ago
      Agreed, streaming services care about customer experience, not the loudness war. But they obviously understand the concept of dynamic range compression -- they employ many professional audio engineers, after all. In fact, they seem to be attracting many of the best engineers.

      The practice of producing highly compressed music recordings will likely always be with us, and that's fine. It's an unnatural sonic character that is now an expected part of the sound of certain genres -- much like jazz guitarists who "degrade" their instruments' sound by turning the treble way down. The people who listen to those heavily compressed pop recordings presumably are pleased with the way they sound, otherwise they'd listen to something else.

      I have to point out, though, that a -15dB LUFS value doesn't mean the sound is "turned down." The -15dB refers to the average K-weighted loudness of an audio file, referenced to 0dB full-scale (FS). That means there's 15dB between the average and peak levels -- and in the case of the charts I've presented, this resulted in boosted volume vs. the original audio. If you change this to -8dB LUFS, you now have 8dB between the average and peak levels, and thus reduced dynamic range and fidelity. So the lower the LUFS standard the streaming service employs, the greater the potential dynamic range. 
  • This commment is unpublished.
    Joe · 7 months ago
    This would have been a poorly researched article YEARS ago when these policies were implemented.  This late to the party, it's more like a time capsule of partial misinformation.

    First, you don't even mention that not all streaming services use normalization, that several who do do including the single largest streaming service in the U.S. have it OFF by default so MOST listeners (in the US at least) do NOT listen that way, or that literally every single track on Billboard stands in stark contrast to what you've written with an integrated LUFS of -10 or less (with most being significantly louder than that) for a list of reasons that you don't even mention.  At best, this is half an hour of research in to years old data paired with an entirely misleading headline and entirely incorrect conclusion.

    Second, it's utter nonsense that CD's necessitate greater loudness.  In fact, you have that completely backward.  CD's have GREATER dynamic range than many of the codecs used by streaming services, and UNLIKE streaming services, listeners are not flipping between your track and other artists instantly, so the entire thing that drove the loudness wars to begin with (skip rate due to loudness bias) is still very much an issue with how countless millions listen via streaming, but is NOT an issue with CD's.
    • This commment is unpublished.
      Brent Butterworth · 7 months ago
      People get so upset about this issue. They seem to get their personal identity wrapped up in it, as if they consider themselves soldiers in some sort of holy war against production practices for music that, for the most part, they don't even listen to. The vast majority of the people who are so outspoken on this issue have no demonstrated familiarity with the sound and use of compressors and limiters.

      Enough ad hominem. Despite having worked for Dolby for a couple of years, I wasn't aware that codecs limit dynamic range -- citation? Also, in the way CDs were commonly used through much of their life -- in CD changers -- people did indeed flip between artists instantaneously. As did radio stations who used CDs as their source, and people who ripped their CDs to make playlists.
  • This commment is unpublished.
    Soundstagenew2021 · 8 months ago
    Hi Brent, I'm not sure how you can say "I guess you can sum all this up by saying that the loudness war is over, and audiophiles won!" when with Apple Music (only something like over 60 million users and only #2 behind Spotify...) normalization is OFF by default and in both Spotify and Apple Music cases (over 300 million users) normalization can be easily turned OFF by the user. There's thousands of posts on Spotify forum and Reddit of users saying normalization turned OFF sounds better (when we know it's just louder). The only way this loudness war can be declared over is when normalization is ON across the board and there is no way to change this setting by the end user.... Given this minor error, I think your article needs to be updated. It's probably a few years pre-mature to declare this over. Things are moving in the right direction obviously but a bit of simple testing will show we're not there yet...
    • This commment is unpublished.
      Brent Butterworth · 8 months ago
      It's not an error. The loudness war had nothing to do with listener behavior (i.e., turning off normalization), it had to do with mastering behavior. If I erred, it's in suggesting there's something new happening here. It's common to see assertions among audiophiles that the loudness war is still raging, but if you peruse the AES E-Library, you'll find that the general consensus among professionals is that the loudness war peaked around 2004 -- four years before mainstream press even started covering the trend. In the 2014 JAES paper "About Dynamic Processing in Mainstream Music," the authors state that while average RMS loudness is 4 dB louder in post-2004 recordings compared with pre-2004 recordings, average crest factor since 2004 has decreased by only 1.4 dB. That's not much, and it can easily be explained by evolving styles and tastes, and by the fact that almost all Top 40 music is produced entirely in a DAW with little or no acoustic recording of instruments.

      I hear audiophiles complaining about the loudness war and dynamic range compression all the time. But I have to wonder how many of them really know how to recognize dynamic range compression, and how they learned? Do they have experience using compression and limiting? Do they appreciate why it's used? Complaining about the state of the recording art and deriding the work of audio professionals seems to have become part of the audiophile identity, but as I've noted many times before, too few audiophiles make the effort to gain in-depth knowledge of audio -- they just read high-end audio publications and forums, rather than reading technical books or joining AES.

      Case in point: see below, a guy who either didn't read or comprehend my article, and who definitely didn't read the article he linked to.
      • This commment is unpublished.
        Soundstagenew2021 · 8 months ago
        "The loudness war had nothing to do with listener behavior (i.e., turning off normalization), it had to do with mastering behavior."

        Normalization is directly influencing mastering behaviour.

        If everything is normalized then the way to 'stand out' on playlists is with dynamic range now. The way to stand out before normalization changed things was louder, to the point of clipping.



        Anyway there's no question everything has been moving in the right direction the last couple years.

        But it's not over yet.
        • This commment is unpublished.
          Brent Butterworth · 8 months ago
          That's what I said in the article.
          • This commment is unpublished.
            Soundstagenew2021 · 8 months ago
            Yeh so it's obvious the loudness war is not 'over' then. And if you listen to Darko's latest podcast with Mastering Engineer he also acknowledges that it is not over, especially with most popular genre of hip-hop for example. So that's one pro audio guy with a different take to the pro-audio gear in your article. I think it's pre-mature to call the loudness war over. We're headed in the right direction though.
          • This commment is unpublished.
            Soundstagenew2021 · 8 months ago
            Here's a discussion among pro's for an album that just won best Engineered album... The one mastering engineer you interviewed for this article may think the loudness war is over but other pro's don't:

            https://www.gearslutz.com/board/showpost.php?p=15306868&postcount=30

            • This commment is unpublished.
              Soundstagenew2021 · 8 months ago
              Correction discussion is for 2017 album 'Colours', so not new. But if you follow that thread, some Grammy nominated pro's there, there is disagreement about loudness war. One pro mentions in that thread: 

              "With regard to loudness, remember if the .wav ain't square the song ain't there."

              So there's no universal agreement about loudness war being over. From the pro's.

            • This commment is unpublished.
              Brent Butterworth · 8 months ago
              Saying the loudness war is over doesn't mean no one's going to create highly compressed mixes. Of course they will continue to do that. It's part of the sound of certain genres now. The "war" notion originally came from the idea that producers and mastering engineers felt they all had to be at least as loud (i.e., compressed) as the previous tune and the next tune -- they were "at war" with each other to see who could be loudest. As the most popular music distribution outlets now effectively penalize highly compressed mixes, there is no longer any need for producers and mastering engineers to be "at war" with each other.
  • This commment is unpublished.
    Jeremy W · 8 months ago
    Yes the Loudness Wars is over and loudness over dynamics won the battle. While I appreciate streaming services adopting a loudness standard (in this case LUFS) it does not solve the issue that the Loudness Wars created. I can a modern slammed recording and achieve the same thing streaming services are doing by putting a track through Audacity and using the 'Normalize' feature. Still sounds terrible, just lower volume. The main issues still lie with modern recording practices all the way up to the mastering phase. LUFS standards need to be present in all stages of the recording process in order for this to be corrected, I believe Mastering Engineer Bob Katz addressed all of this in the following article published 7 years ago: https://www.soundonsound.com/techniques/end-loudness-war
    • This commment is unpublished.
      Brent Butterworth · 8 months ago
      Bob Katz didn't author that article and doesn't address anything in it. The first paragraph merely quotes him as saying, "The loudness wars are over," and the article mentions him only a few times after that -- a very small part of an article that's somewhere around 9,000 words with the sidebars. The article basically agrees with Katz's statement and what I've said, and presents many examples of best practices employing the then-new volume LUFS standard and normalization practices. Yes, there are lots of overly compressed mixes still out there, but it's likely that the popular ones will be remastered, and as the article points out, it will be increasingly less likely that these mixing practices will continue into the future.
      • This commment is unpublished.
        Jeremy W · 8 months ago
        I find it highly doubtful that popular music will be remastered again... the recording industry does not want to spend the money to do that. It has been at least 10 years now that we have had streaming platforms in our environment and the recording industry has done little to nothing at all to adapt to loudness standards. The excuse for continuing to follow archaic mixing/mastering processes is always going to boil down to "a purely artistic and musical decision" which is a shame. While streaming platforms have taken a great approach to begin correcting the Loudness Wars, it is only the first step. The recording industry needs to be reeducated and begin to adapt to modern standards that are already a decade old.
        • This commment is unpublished.
          Brent Butterworth · 8 months ago
          "The recording industry needs to be re-educated." Unless you can share your identity and CV, and establish your authority to make such a statement, I doubt that people who make a living in audio recording will be eager to queue up for your re-education program. As noted in the AES paper cited above, audio enthusiasts didn't seem to notice that recordings were being heavily compressed until 4 years after the peak of the loudness war, when publications started telling them they should be concerned about it. I have to wonder how many of the enthusiasts complaining about DRC have any experience in audio production and even know what compression sounds like?
          • This commment is unpublished.
            Jeremy W · 8 months ago
            I don't need to provide my credentials in this debate. Technology is ever changing and we seep further and further into a digital realm with new hardware, software, plugins, etc being created every day. Do you not think it is important for everyone to continue educating themselves to adapt to the latest technologies that are out there? If you argue that audio enthusiasts only realized 4 years ago that recordings were heavily compressed then why has the Loudness Wars been a recognized and ongoing issue since 1994 when Oasis released 'Definitely Maybe'? I agree with your statement that many enthusiasts do not have much experience with DRC. But many can hear the effects of it, they just don't know how to describe why it sounds the way it does nor would they understand how that result was achieved. I would argue there are many professionals in the industry that don't fully understand DRC and again, education is the answer to resolve this. I appreciate you posting the original article and replying to me on my comments, again I think it is a great first step for Streaming Platforms to integrate a loudness standard. There's more work to be done on the industry side if we want to truly make the statement that we "Killed the Loudness Wars". Thank you.
            • This commment is unpublished.
              Brent Butterworth · 8 months ago
              I think when you say an entire industry needs re-education, you do need to present some evidence that you are familiar with standard industry practice. If you read pro audio publications, you'll see that awareness of this issue is very high and that it's a common topic of discussion. Also, I wrote "audio enthusiasts didn't seem to notice that recordings were being heavily compressed until 4 years after the peak of the loudness war"; please read the AES paper I cited. https://www.researchgate.net/publication/269102263_About_Dynamic_Processing_in_Mainstream_Music
              • This commment is unpublished.
                Jeremy W · 8 months ago
                Again, there is nothing wrong with educating ourselves on the latest technologies. If we didn't do this we would still be using a 100% analog chain for all stages of recording. Thank you for providing the link to the document, I overlooked it initially. After reviewing it I still do not see anything new, mainly it shows that the Loudness Wars started in 1989 and continues on to this day. They set 2008 as a year where it finally catches media attention and I would argue that many already knew the Loudness Wars existed well before this timeframe. The increase of social media, web forums & video stream platforms are certainly a good reason why they chose that number. I guess we will have to agree to disagree on the whole debate. I truly hope you are right that mixing and mastering practices change, we're going on 10 years of Streaming services being available and I have seen no change in recording industry practices to adapt and conform to modern stardards. The volume can be lowered on hyper compressed, clipped, limited and distorted music but what's the point when the damage is already done?
                • This commment is unpublished.
                  Brent Butterworth · 8 months ago
                  I agree with your last statement, it's 100% correct. But what makes you believe the recording industry is not educated on the latest technologies? There's considerable discussion of it in pro audio publications, and there has been for a long time -- the article you cite is from 7 years ago. I find it frustrating when an anonymous person with no experience in a field feels the need to tell professionals how to do their job. Show some respect. I know and have worked with a lot of recording pros and they are not the ignoramuses you and so many audiophiles seem to think they are.
                  • This commment is unpublished.
                    Jeremy W · 8 months ago
                    I guess I'm looking at it from the perspective of a musician walking into a recording studio and seeing some of the current trends going on. It scares me when I have had to question the choices of a producer, a recording engineer, a mixing engineer and a mastering engineer on why they did things a certain way and the answer I repeatedly get back is that's how they do it. They clearly missed out on the 5 w's and 1 h lesson when it came to applying certain processes and adding tools. Thankfully they all listened to artistic input and we achieved the desired results. So it makes me question more who is responsible for pushing these trends to continue, The artist? The record labels and execs? Why is there such little discussion on preparing an album or a song to conform to loudness standards that are in effect? Again, I am quite thankful for your article as I believe it touches on that point and hope it increases awareness of the subject to everyone. I apologize if I have offended you in any way, my intent was to have a healthy debate on the statement of the Loudness Wars being over. If anything it's just gone stagnant. I appreciate your replies and thank you for your discussion on the matter.
  • This commment is unpublished.
    Mark Waldrep · 10 months ago
    As an experienced mastering engineer, I worked on over 500 albums from classical to jazz and rock to country projects. I'm not sure it's safe to say that the loudness wars are over. The over use of mastering compression and trick like ultramaximizer are still the norm. I mastered the Bad Company "Merchants of Cool" album with Paul Rogers in the room with me (a very nice guy!) and his engineer. Both gentlemen were very pleased with the end product BUT the label was not. The artist was happy but the label insisted on reducing the dynamic range and making the tracks louder. They insisted 5 times until the dynamics were non existent! I gave up mastering after that experience. It's true that streaming changes the game but the files that are coming out the mastering facilities are only slightly less crushed. The war continues.
    • This commment is unpublished.
      Mark Phillips · 10 months ago
      It doesn't help when mix engineers like Andrew Scheps *mix* so loud that mastering engineers complain about having no headroom to work with.
    • This commment is unpublished.
      Brent Butterworth · 10 months ago
      Hi, Mark. You're citing a 2002 album, which was certainly in the midst of the Loudness War. Of course, most of those masters of that era are still available in CD or digital download. But now that the primary method and technology of music distribution has changed, and in 2011 we got an industry standard for average volume measurements, maybe it's changing? There's no reason to slam those files if they're going to go on Spotify and your peaks top out at -10 dBFS.
      • This commment is unpublished.
        Doug Schneider · 10 months ago
        Is anyone in the pro industry more or less "tracking" this to see what's being done? I know there were some dynamic range sites a while back, but is anyone trying to act like a watchdog?

        Doug
        • This commment is unpublished.
          Brent Butterworth · 10 months ago
          I haven't found a website that tracks this stuff. I do intend to do some measurements on it in the future.
          • This commment is unpublished.
            Mauro · 10 months ago
            Looking at this website with recent albums on top doesn’t seem to support the hypothesis of the article but I am not sure it is a trustworthy source
            http://dr.loudness-war.info/album/list/year/desc
            • This commment is unpublished.
              Brent Butterworth · 10 months ago
              I'm planning on doing more research into this, doing measurements on actual streams from streaming services. On Doug's FB posts, I've seen commentary from pros saying, in effect, yeah, this is a trend, but a lot of new mixes are still very crunched.

              This Loudness War site has always seemed a little dicey to me. It relies on reader submissions, and thus isn't a valid sampling. It's also taken almost entirely from CDs and downloads (although the sources of the downloads aren't specified). What I dislike the most, though, is that it seems designed to inflame audiophiles' sense that the record industry is victimizing them. The audiophile publications already do a great job of that! :)
          • This commment is unpublished.
            Daniel · 9 months ago
            It's enough to go to youtube, right-click on a video and select "Stats for nerds". This will show video statistics and one of the things there will be "Volume / Normalized". I just clicked through a few videos on youtube's "Pop Hotlist" list and most of the things there have loudness 5 dB and more over the target.

Latest Comments

Ragav 18 hours ago HiFiMan HE400se Headphones
Hi Brent! How is the build quality on the HE400SE? Lots of people complaining about ...
It’s an interesting topic. That’s good that someone has tried to technically define it. 

I have ...
Brent Butterworth 1 days ago Eardrum Suck: The Mystery Solved!
@BrianI apologize, this one escaped my notice. Yes, with the Bose, the eardrum suck only ...
Brent Butterworth 2 days ago Shure Aonic 215 Gen 2 True Wireless Earphones
@MauroThe TW2 is what comes with the Aonic 215 Gen 2. I can't say anything ...
@Brent ButterworthThanks for confirming. 
In the meanwhile I found this on Head-Fi: “only the TW2 allows for ...
Brent Butterworth 3 days ago Shure Aonic 215 Gen 2 True Wireless Earphones
@MauroHi, Mauro. Just had a chance to try this, and the EQ did work with ...
Hi Brent,
Interesting product and review!
A question about EQ. I read a user review and also ...
@QtaxIs it permanent pressure on your ears even when you take the headphones off?

Brent Butterworth 9 days ago Shure Aonic 215 Gen 2 True Wireless Earphones
@GuestThanks! And thank you so much for the tip on the adapters. Just ordered a ...