Justin Bieber

If you’ve heard “Boyfriend” from Justin Bieber’s “Believe” album, you realize that the teen heartthrob is evolving musically. He’s still mainstream pop but not as bubblegum as his “Baby” days. He’s also incorporated more elaborate stage sets and effects (he hired Phish’s light designer) for his second arena tour, which features “Call Me Maybe” sensation Carly Rae Jepsen as opening act. She’ll return during his set to duet on “Beautiful,” their ballad that’s already a hit in their native Canada. Read an interview with Jepsen at startribune.com/music. Jon Bream