Hi, Chris; The number depends on a couple of things. First is the format of the music, I store music in MP-3 format at a bit rate of 128 kbps. Second is the length of the song. My 'Mamas and Papas' file runs from 1.1 to 6.8 Mbps so if we say an average of 3.2 Mb we are looking at about 10,000 songs. My Fleetwood Mack file is pretty complete and is 3.4 GB. Other formats use a lot of space, like 'wave' and 'flac'. The say they sound 'better' but I don't know. Good luck, let us know what you think.