Brooklyn indie experimenters Grizzly Bear are no strangers to Bonnaroo, this year moving up to the smaller of the festival's two main stages for their Friday afternoon set. Taking the Which Stage to a backdrop of suspended candles, the four-piece (joined by touring keyboardist Aaron Arntz) launched into "Speak in Rounds." The set was dominated by new material from last year's Shields, though the crowd was appreciative of throwbacks like Yellow House's "Knife" and "On a Neck, On a Spit," as well as a handful of Veckatimist tracks. Never overtly catchy, the set may have been a demanding one on festival stragglers sitting in, but onlookers that hung around long enough were treated to a special guest appearance from Solange. The R&B singer joined the band for "Two Weeks," which was a stand-out moment in a set of songs that occasionally drifted together too closely. Her attempts to get frontman Ed Droste to dance with her were endearing to watch, in spite of the awkwardness, and her voice was a beautiful addition to the track. The guys in the band are certainly talented musicians, and Droste made a few attempts at banter (including telling the crowd about an experience on a mechanical bull in Nashville the day before). But while Grizzly Bear deliver a professional and technically impressive show, there's an element of excitement that's just missing, especially in front of a crowd this size.