Who sing the songs before football games?

It varies from team to team as well as what traditions they have for the game. In the SEC the Arkansas Razorbacks for instance all "Call The Hogs" and then for every kickoff they do a shorten "WOOOO PIG SOOIE" call as the ball is sent from endzone to endzone during the kickoffs.

At Tennessee they play "Rocky Top" , etc....It just varies on the team.