By the Mayan calendar, 2012 was supposed to have been apocalyptic. By the measurement of music mastering engineers, however, it was instead a turning point in the history of how good iTunes music can sound. That’s because file-based music and iTunes in particular now have the tools needed to make AAC mp4s and other compressed file formats sound far better than they have in the past.

“This year it’s different, this year it all changed,” exclaims Eric Boulanger, a mastering engineer and manager at the The Mastering Lab, a Los Angeles studio facility where records receive their final polish before distribution. The facility, where artists including the Eagles, the Rolling Stones, Al Jarreau, James Taylor, Willie Nelson and Lyle Lovett have had their sounds perfected by mastering legend Doug Sax and his staff, was the first to employ Mastered for iTunes, the software toolkit released earlier this year by Apple and developed with significant input from mastering engineers affiliated with The Recording Academy’s Producers & Engineers Wing.

“There’s been a movement towards this for some time now,” Boulanger continues. “The market has been demanding higher-quality sound. You see it in the resurgence of vinyl: vinyl records are being bought by teenagers who, other than maybe a few times in their lives when they’ve listened to a CD, have spent their entire lives experiencing music through mp3 files and earbuds. When they hear what music can sound like on actual records played through speakers, they say, ‘We want that!’”


New Tools

And that’s what everyone will soon have access to, thanks to new tools that let mastering and other audio engineers approach file-based music formats as their own entities, instead of simply taking the 44.1 kHz/16-bit .wav files that are the basis for Compact Discs and jamming those larger files into the confines of a 128-kb/sec or 256-kb/sec file. Andy VanDette, chief engineer at New York’s Masterdisk who has mastered records for artists including Rush and the Beastie Boys, says attention began being paid to the mastering of music files when artists began to complain about how their recordings sounded on iTunes. “It took a long time for the market to pay attention to how file formats affect sound quality,” he says. “But then artists began to tell us, ‘This doesn’t sound like my music anymore,’ when they heard it on iTunes.”

According to Boulanger, Apple’s own engineers had been looking into the issue of how data compression affects music for a couple of years. However, computer engineers understandably would look at a challenge from a coding point of view, not necessarily from an artistic perspective. When they began to collaborate in earnest with members of the P&E Wing, progress accelerated. It reached a turning point in January 2011, when Colbie Caillat’s producer (and father) Ken Caillat met with iTunes executives to discuss how to improve the sound of Colbie’s music when it was distributed through the iTunes store. Ken Caillat referred Apple’s people to Boulanger, who conveyed to them his concern that since the iTunes’ encoding process to the AAC file format took place after the mastering stage was completed, the esthetic intentions of the artists and engineers for the music could be distorted by the additional data processing. He suggested that if Apple could make that encoding process more transparent, and offer access to it to mastering engineers before it was delivered for AAC encoding, music could better accommodate the process. The ultimate goal, Boulanger says, was to establish iTunes as a primary format for mastering purposes, on a par with the CD and vinyl, rather than as an afterthought.

From that larger collaboration Apple created Mastered For iTunes, a software kit that lets artists and engineers preview how their tracks will sound once they are encoded for iTunes, allowing them the opportunity to make informed decisions regarding levels and how hard to hit the AAC encoder, thus adapting the music for the medium ahead of the iTunes encoding process. Mastered For iTunes also standardizes certain protocols suggested by mastering engineers, such as delivering masters at 24-bit resolution.

A combination of new tools and a heightened awareness of what’s necessary to make music sound good on files is opening a new chapter in music production. The dialog opened around the mastering of Colbie Caillat’s LP All Of You led directly to the creation of a toolkit from Apple now downloadable by anyone who wants to optimize their music for iTunes distribution. It reflects insights offered by collaborating engineers, resulting in tools such as AFClip, which allows engineers to measure whether or not a high-level master will clip the encode and decode stages of AAC, causing distortion.

Apple’s cooperation was critical -- in the second quarter of 2012, by Apple’s own estimate, iTunes accounted for 64 percent of the entire digital music market and 29 percent of all music sold at retail (including both digital and physical formats). And the company, often known for its diffidence to outside collaboration, cooperated by making its ALAC (Lossless) encoding process transparent. It has not only embraced the quest to improve the overall sonic quality of file-based music but has included in the on-line toolkit, AU Lab, a free digital audio application that can be used to perform key quality-enhancement tasks such as detecting peaks and clipping, and performing double-blind listening tests. This injects optimization for file-based distribution further up the music production chain and, combined with Mastered For iTunes, will take sound quality even further.

“Apple is huge in music, so when Apple changes, the entire industry changes,” says Boulanger. What consumers can expect as Mastered For iTunes becomes more ubiquitous is a big change, too -- a change for the better.

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