The biggest surprise of the weekend was Joywave, who are riding the wave of their burgeoning hit "Tongues" (their previous stop was a performance on Late Night). The young band's set proved their success is hardly a fluke. All their songs are as fun as their best ones; their chemistry makes them compelling and their time on the road has made their set seamless. While the shaded grove of the BMI stage is often the favored place for dads to nap between sets, Joywave brought the disco to the forest, moving the kids that comprise their fanbase, as well as their parents (and other folks old enough to appreciate a band using Upstairs at Eric's as a template), who ran "this is my jam!"-style down the embankment to boogie in the pit with their kiddos. One of few bands at the festival this weekend who seemed as capable of connecting with an audience as they were entertaining them.