Macsome Audio Editor Freeware
It is a freeware which can quickly edit MP3 & AAC files on your Mac.
Audacity is free, open source, cross-platform software for recording and editing sounds.
Ardour is designed to be a free and fully blown DAW. It requires a little more setup and has a higher learning curve than something like Audacity, but is very powerful and is used
Know any negative aspects of this option?