AAC vs LAME Mp3 Battery drain on Sony E series Options

[zvnteq777]

Hi, I have a Sony E353 walkman mp3 player (also plays ogg, aac, flac, etc) anyway, I was thinking of converting my library to AAC 156kbps VBR but I was wondering if that or LAME q3 would drain the battery more, at identical bitrates, let's say 128 CBR for both AAC and LAME Mp3 (I'm using version 3.98.4) which would be a bigger drain on the battery?

Thanks so much for your help

[Brand]

Don't know about the Sony walkman, but on a Nokia N79, testing the CPU usage I got this (most to least CPU usage):
OGG Vorbis>>>>>AAC>>MP3>FLAC

So OGG used the most CPU by a significant margin, while the other 3 were more close. AAC still appeared noticeably higher than MP3, while MP3 and FLAC were very close, the latter being just slightly more efficient. But this was just a quick test, I might do something more thorough at some point. I used variable bitrate for all of them. (around 150-200kbps for the lossy codecs, IIRC)

[Brand]

Don't know about the Sony walkman, but on a Nokia N79, testing the CPU usage I got this (most to least CPU usage):
OGG Vorbis>>>>>AAC>>MP3>FLAC

I later did a more thorough test. If there's an MP3 advantage compared to AAC it's actually minimal and/or the CPU usage for those might not be reported accurately if they use a dedicated/native decoder.

Testing the battery life itself is something I'm not planning to do for now. I once let some tracks play through my headphones overnight (about 10 hours, in offline mode) and the battery indicator didn't even lose a bar (out of 7). So it would take several days to drain the battery and I'm not sure I could reliably measure the differences.