The Lost Song

Lost Song is a song in Halo: Combat Evolved that doesn't appear on the soundtrack. It is played during the level Assault on the Control Room right before the bridge that overlooks the Control Room. You must go across the bridge with the two banshees. Once you enter the other room the music will start playing. It is endless, as it repeats after the "end," so you can listen to it for quite some time. Note that there are Covenant in this room that may pose a threat in harder difficulties. If you wish to continue listening to the music do not exit this area, as the music will end at once.