mpTrim mpTrim (formerly mp3Trim) is a simple and easy to use MP3 editor. Its main advantage is that it works directly in the MP3 format without having to decode/re-encode, so it is very fast and doesn't degrade the music quality. It can trim the parts that you want to discard. It can adjust the volume - either manually or automatically - for example, to amplify those pesky MP3s that were encoded too low. It can fade-in/out abrupt beginning/ending. It can clean up your MP3s and recover wasted disk space.