RhythmCat is a music player which can be running under Linux. It can be used as a normal music player, and it can also show lyrics in a single window, or even on the desktop. It can help you mix your voice into the original music. And this player can help you convert the format of your music files, or cut/join your music...
Install RhythmCat in ubuntu
Download deb packages from here once you have deb packages you can install them by double clicking on it.