Most of you don't seem to be aware that re-encoding MP3 files (to AAC, for example) further lowers audio quality... a lot, depending on the bitrate settings of the MP3 & AAC encoders.
Btw, the choice of codecs is relevant, too. I find the LAME MP3 codec to be MUCH better than most others I've heard. You find it in some freeware applications, too. "Max" for OSX, for example: http://sbooth.org/Max/
Generally, AAC is more efficient, meaning that smaller AAC files usually sound as good as equivalent MP3 files 130-150% their size. So generally there's nothing wrong with AAC... the re-encoding of your MP3-libraries is the problem.
Currently playing: NSMB (Wii)







