Battery life – MP3 vs. DRM WMA
I just completed some battery life tests on my new 4GB Clip and the results were not what I was expecting. The executive summary is that standard MP3 audio gives much greater battery life than for DRM WMA audio. I ran a test to determine the battery life, mostly to see if my new device had a problem and needed to be returned. After a full charge, I played a 20+ hour OverDrive audio book (DRM 32kbps WMA). The Clip went 12 hours 18 minutes before being fully discharged. It’s easy to determine the time by using the “Resume?” option for audio books. This was disappointing and I was suspecting that I had a bad device. So, I ran a second test trying to set it up in a mode that would give me the best possible battery life result. I ripped a CD to 128k MP3, transferred to the Clip, and had it play the album in a loop. It lasted 17 hours 33 minutes! That’s a big difference.
I don’t know if the significant factor is the bitrate, WMA format, or the DRM, but I am suspecting the DRM. I suppose it’s possible that you may need to fully discharge the battery before fully charging to get the best results, but I have a hard time believing that.
Testing details: FW was 18a then upgraded to 29a. None of the defaults were changed. Sample music was removed from device then the Clip was formatted via the Settings menu. OverDrive audio book was downloaded to Audiobook folder. JVC fx66 earphones installed – volume, as with everything else, still at default. I disconnected from the computer and started the audiobook. For the MP3 test, everything was the same except I started the play while still attached to a USB charger (not a computer) and waited until the display went dark before disconnecting.