One of out HOTTEST acts in STB history… literally! Will Calvin be returning for STB show No.3? This image appears in the gallery:Who's On The Summertime Ball Line Up? Check Out The Most Popular Performers In STB History (2009 - 2014) 9. One of out HOTTEST acts in STB history… literally! Will Calvin be returning for STB show No.3? Picture: Derek Bremner 19 images See the full gallery: Who's On The Summertime Ball Line Up? Check Out The Most Popular Performers In STB History (2009 - 2014)