When users take the specifications of an MP3 player into consideration, one very important factor most take into account is the rated battery life. However, as many are aware, the battery life stated is generally the runtime from a full charge in ideal conditions, such as when the player is left playing without any sound enhancements (EQ, bass-boost, etc.), volume set to a moderate level, all music is 128kbps MP3, backlit display goes out within a few seconds and so on. However, according to tests conducted by CNET, they found that while many players met or exceeded their claims, one feature that has a drastic affect on battery life is the infamous DRM.
When it comes to the Creative Zen Vision:M's 14-hour claim, CNET got about 16 hours of playback time with MP3s from a full charge, which was a nice surprise. However, when they tried playing WMA 10 DRM crippled subscription tracks on it, they only got just over 12 hours; a loss of almost 4 hours (~25%) of playback time due to the battery-hungry DRM. CNET found similar results with other players with WMA DRM drastically reducing battery life by up to around 20%. Apple's FairPlay DRM seems to have less of an effect with battery life being reduced by around 8% when compared with MP3 playback.
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The full article can be read here. |
When it comes to maximising battery life in a portable MP3 player, this is a clear sign that one should avoid playing DRM protected music if at all possible and also another good reason to get the music converted into a more battery-friendly format. While 2 to 4 hours may not seem a lot to some people, this can be the difference between listening to music to the end of a lengthy journey or getting left in silence a couple of hours before the journey is complete.
With the shorter battery life caused by DRM, this means that consumers have to recharge their battery more often, which in turn results in a shorter overall battery life before it needs replacement. Finally, while most MP3 players now have a rechargeable battery, for those who still use disposable AA/AAA type batteries and listen to copy-protected music, not only does DRM cut their listening time, but it also costs them more in replacing batteries, not to mention more battery waste building up in landfills (if not recycled).
Source: c|net News - MP3 Insider



I can't see listening to music that long even on a long plane ride. Plus, especially driving or riding in a car, you'd have the ability to re-charge the battery if not use a car lighter adapter (don't MP3 players have adapters to allow them to recharge and play through the lighter?)