It's also possible that he used the empeg as a file taxi and has some big files on there that aren't visible through emplode. You could check it out with an ftp client, maybe, but if you don't care what it might be, assuming that this guess is correct, it'd be easier to just do the disk builder thing, probably.

And it probably isn't right anyway, as if his taxied files were that big, he'd have had no more space to put mp3s than you do now.