iTunes Sound Check:
Weak Link in the Loudness War Chain?
If we assume that the loudness war is at least sometimes problematic, pressuring mastering engineers to compromise audio quality in the belief (warranted or not) that hypercompressed recordings sell better, then where is the weak link in the loudness war production and distribution chain? Where is the loudness war's Achilles' heel?
I propose that Apple could seriously undermine any remaining justification for the loudness war simply by setting the default status of the iTunes Sound Check function to "On".
If Sound Check normalizes every song to approximately the same loudness, then there's no financial advantage to using compression to try to make your song louder. If someone prefer hypercompression for aesthetic reasons, fine, but this removes the profit motive that has been the primary factor driving the loudness war.
As Orban & Foti pointed out, there's already little to be gained by hypercompressing music for radio broadcast, because radio stations already do a pretty good job of squashing the music; additional compression often just makes music sound small and distorted. By changing approximately one line of code per platform, Apple could add iTunes, iPod, iPad and iPhone to the list of platforms for which hypercompression becomes basically pointless in terms of music sales. Hopefully other manufacturers would follow suit.
To the extent - admittedly speculative - that the loudness war has been one of the factors behind the decline of the music industry, this move could be to Apple's (and the overall industry's) advantage. Customers who have been turned off by music that doesn't "breathe" might start tuning back in. Currently, however, many or most customers leave Sound Check at its initial "Off" setting. By defaulting it to "On", Apple could also protect them (and their ears) from extreme loudness discrepancies between recordings from different eras.
Certainly, Apple needs to ensure that Sound Check is as close to acoustically transparent as possible, and it should default to "album mode", preserving intentional dynamic changes between songs on the same album. Properly done, loudness normalization will generally be nothing more than a fixed gain change. If a recording has extreme dynamics (a rare problem these days), some light limiting may be needed to avoid clipping - this can and should be done carefully.
In any case, loudness normalization should be far less destructive than the loudness war itself. The average consumer is likely to welcome consistent loudness from one song to the next, and individuals who are concerned that Sound Check might "do something" to their music are welcome to override the default, just as those who want to take advantage of it are currently forced to do.
This is not a new idea - Bob Katz, Wolters et al, Greg Calbi, and others have made similar observations. Apple is the 800 pound gorilla in the music industry today, and the only player that can have this large an impact. Many of us who work in the consumer electronics industry know people who work at Apple; I propose that we gently and politely lobby them to consider this change.
Earl Vickers, email@example.com