With all the furor over DRM lately, CNet asked itself the simple question, “How does DRM affect battery life on your iPod?” As you might expect, the answer is — badly.

CNet has looked at numerous mp3 players, including the iPod, the Zen Vision and Sony’s new Sony Walkmans, first establishing their peak battery life when playing unprotected MP3s and then comparing them to battery life when playing nothing but DRM-protected formats like AAC or WMA. The results are extremely discouraging: for example, on the Creative Zen Vision, you lose 25% of your battery life when playing WMAs over unprotected MP3s… and that’s without putting the backlight on.

Granted, there’s a lot of other things that will drain your mp3 player faster: playing higher bitrate files, using the backlight, watching videos or even using more powerful headphones. That extra processing power and therefore more juice are required to decode protected files isn’t terribly surprising. Still, it’s another bullet point on why the industry’s push towards DRM sucks for consumers.

MP3 Insider: The truth about your battery life [CNet]

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