What is the “Loudness War”?
One thing that makes me sad is the bad sound quality of some new music albums released on CD or on iTunes.
The problem with many late CD releases is that they are overly compressed. By “compressed” I mean dynamic range compression (which reduces the difference between loud and low parts of the music), not digital data compression (which reduces the size of digital audio data).
The main reason for overly compressed music is that the record companies want the music to be as “loud” as possible because they think consumers will prefer louder CDs over ones with lower levels. Hence the name: “Loudness War”.
Since the peak level of the music is controlled by the user the record companies try to raise the average level by making quieter parts louder. But if you make the quiet parts louder while the peak stays the same you reduce the difference between quiet and loud parts—you reduce the dynamic range.
The Problem:
The problem is: Overly compressed music sounds flat and lifeless. Transitions, e.g. between verse and chorus vanish, as does the sense of depth. The music has no real punch. My impression is that loud bass sounds (e.g. bass drums) appear muffled or mushy. Sometimes the music sounds harsh and distorted.
Over the years the average levels of CDs have constantly increased which has decreased the dynamic range. The loudness war has thus lead to the perverse outcome that older releases often have a higher sound quality than newer ones, and also that LP releases often sound better than CD releases (because on LPs there are technical limits to audio compression). In the case of Metallica’s Death Magnetic even the version in a computer game sounds better than the CD version.
The effects of the loudness war are well demonstrated in the following two videos (one short, one longer video).
1. “The Loudness War” by Matt Mayfield on Youtube.
A high quality version of this video (20MB Quicktime) can be downloaded from this page. (Here is the direct link.)
2. “The Loudness War: Background, Speculation & Recommendations” from Earl Vickers on Vimeo.
Comparison Between Strong and Weak Compression: Examples
If you have a good stereo (such as this one) you will really appreciate music with a high dynamic range. But even on my laptop speakers I can hear the difference.
Here are links to comparisons between more compressed and less compressed versions of three songs:
Measuring Dynamic Range
The dynamic range of an audio file can be measured. The “Pleasurize Music Foundation” provides a Dynamic Range Meter software that will calculate for any given song a DR value. The software can be downloaded from the Dynamic Range Database (following the link look in the top right corner).
The DR value is not only dependent on audio compression but also on the type of music or audio. And of course the dynamic range is just one element of audio quality. Nevertheless generally you can say that the higher the DR value the better or at least the more hi-fi the audio material.Addendum:
Apple’s iTunes Music Store has some guidelines for mastering engineers regarding dynamic range in their “Mastered for iTunes” program. Hopefully the music in this program will have a higher dynamic range than the music released on CDs.
Addendum 2:
I think “Mastered for iTunes” is generally a good idea and some of the releases have exceptional sound quality. But unfortunately that label is not a guaranty for good sound quality. All depends on the record producer. If the producer delivers a bad master then also the “Mastered for iTunes” release will be bad.
For example Red Hot Chili Peppers’ album “I’m With You” is labelled “Mastered for iTunes” but some of its songs (e.g. “Monarchy of Roses”) have a dynamic range of DR3. That is an abysmal value. Of course it also has no headroom and horrible clipping. It seems that Apple does not reject songs if they are not mastered according to their guidelines but accepts them blindly and labels them “Mastered for iTunes” as long as they get the data in 24Bit/96kHz. The CD version can’t be much worse if there is not only noise to hear. If you want to buy that song, I would recommend buying the LP. The version on vinyl is better. It seems absurd that in the digital age you have to buy analogue LP’s to get a reasonably decent sound quality. But in some cases that is the sad truth.
