From the ever wonderful MIX Magazine:
The Loudness War is OverA lot of selections at ITunes or Amazon downloads are available for MP3 at one price and a lossless file format for a little bit more. This is not the text of the article -- the article is about dynamic range and compression and the effect this has on the long-term listenability (and market value) of the music being offered for sale. Some artists 'get it' but a lot of artists do not bother (or cannot tell the difference -- this scares me). A lot more at the article -- worth reading about if you love music...
I was at the AES show in San Francisco last November and I came back with renewed hope for the future of the music industry�not just from a business perspective, but from a recording-quality perspective as well. Besides the usual discussions about gear and recording techniques, there was a lot of talk about high resolution digital downloads surpassing CDs as the dominant delivery format within the next few years. Optimism is growing as more and more engineers are seeing a way to finally get past the loudness war.
Wait, the loudness war is over? Well, there are still plenty of soldiers who still haven�t gotten the message but the wheels are in motion. It�s just a matter of time now.
Consider this: The current loudness war is a product of the CD format and the ability to play a song from CD �A� next to a song from CD �B�. Since the music industry has never adopted loudness standards (like the long established standards in film and broadcast) we�ve been left to fight it out for ourselves. No artist wants his or her music to sound quiet next to other music. It�s human nature. So just to make sure, we�ve made �em loud�louder every year.
But here�s the thing: The future of music delivery is not the CD. Sure, the CD will be around for selling offstage and at gift shops, but the CD is on its way out as the dominant delivery format. How many young music buyers actually buy CDs? How many artists� primary delivery format will be CDs when the recording school graduates of 2011 are in the prime of their careers 10 years from now?
File based delivery is the future. Whether it�s iTunes, Pandora, iPods or whatever, file based playback is how most people listen today and it will completely replace the CD in the very near future.
Remember to disambiguate between "compression" when it means reducing the dynamic range (difference in level between the loudest and quietest parts of a song) and "compression" when it means reduction in the data-rate to carry the same music.
There is a concept in information-theory that data can be described by its "entropy". A high entropy data file will not lose much volume when turned into a .zip, but a low-entropy file will. JJ Johnson, a genius from Bell Labs, extended the concept to data-rate when using lossy coding like MP3 is used, and called it "perceptual entropy".
P.E. basically tells you how much information-carrying capacity you need to have transparent
audio quality -- no audible difference between the original LPCM (CD) recording and the MP3.
And frankly, for many artists, the P.E. of their output is well below the 128 kbps of a typical download.
So is it at all surprising that they cannot discern the difference? MP3 is not inherently bad, it is only bad when the P.E. figure shows us that the needed data-rate exceeds the available data-rate.