Jay-Z kicked off the weekend with a surprise intimate pre-show ahead of his Roots Picnic headlining set . A select group of fans and friends were invited to the event, which was held at Philadelphia venue The Foundry on Friday (May 29). Despite not being a full concert, the performance was a preview of what Roots Picnic attendees can expect the following night. The Roots backed the 25-time Grammy winner during the event, just as they will at the music festival. While Hov performed his classics like “U Don’t Know” and “Big Pimpin” to commemorate the 25th anniversary of his landmark album The Blueprint , his wife and Everything Is Love collaborator Beyoncé danced in support. Also championing the set was rapper Talib Kweli, who teased in a Facebook post that Roots Picnic guests were "in for a treat” when the show goes on at Belmont Plateau in Fairmount Park. Roots Picnic won’t be Jay-Z’s only live engagement this summer.…