Chances are good that, if you're over 30, you've never even heard of this guy. But if you're among the younger crowd — well, that's a different story. Puth's been making music out of L.A. for about two years now, and he's already got a handful of hits, including "See You Again," "One Call Away" and "Marvin Gaye" (with Meghan Trainor). His accolades include a couple of Teen Choice Awards, two American Music Awards and an MTV Video Music Award. "It's soulful music, with a bit of hip-hop, and lyrics that hopefully everyone can relate to," Puth says of his music. Want to know if you'll like it? Ask your kids. (It's worth noting that the big concerts at the fair have often skewed younger — last year's acts included Fifth Harmony, and a few years back, a young Justin Bieber, in the early stages of Biebermania, took the stage in Timonium.) 8 p.m. Sept. 3, on the racetrack infield. $50 (includes fair admission).