Several of the test subjects went so far as to tell they felt more confident expressing a preference while listening to the Apple buds. The biggest surprise of the test actually disproved our hypothesis: Eight of the 10 participants expressed a preference for the higher-bit rate songs while listening with the Apple buds, compared to only six who picked the higher-quality track while listening to the Shure's. The tests were administered double-blind, meaning that neither the test subject nor the person conducting the test knew which tracks were encoded at which bit rates. We then tested using the SE420's and asked the participant to choose between Track C, Track D, or to express no preference. We asked each participant to listen with the Apple buds first and to choose between Track A, Track B, or to express no preference. We were confident that the better phones would make the task much easier, since they would reveal more flaws in the songs encoded at lower bit rates. We hypothesized that no one would be able to discern the difference using the inexpensive earbuds (MSRP: $29) that Apple provides with its product, so we also acquired a set of high-end Shure SE420 earphones (MSRP: $400). (See the chart at the end of the story for details.) We were hoping participants would choose a diverse collection of music, and they did: Classical, jazz, electronica, alternative, straight-ahead rock, and pop were all represented in fact country was the only style not in the mix. We used iTunes to rip the tracks and copied them to a fifth-generation 30GB iPod. We asked each participant to provide us with a CD containing a track they considered themselves to be intimately familiar with.
Four participants have musical backgrounds (defined as having played an instrument and/or sung in a band). Eight are editors by trade two art directors. Our 10 test subjects range in age from 23 to 56. So we decided to test a random sample of our colleagues to see if they could detect any audible difference between a song ripped from a CD and encoded in Apple's lossy AAC format at 128K/s, and the same song ripped and encoded in lossy AAC at 256Kb/s.
We're all for DRM-free music, but 256Kb/s still seems like a pretty low bit rate-especially when you're using a lossy codec. 128Kb/s) and charging a $0.30-per-track premium for it. Apple's iTunes store-in partnership with EMI-is now hawking DRM-free music at twice the bit rate of its standard fare (256Kb/s vs.
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