John Mayer, celebs go 4th in Philly

John Mayer at the Liacouras Center. (Steven M. Falk / Staff Photographer)

John Mayer played a secret show at the Liacouras Center last night for winners of a SiriusXM radio contest.

It's the final dress rehearsal for his upcoming tour, which hits the Susquehanna Bank Center on Aug. 23. Mayer is in town now to headline the Roots-curated 4th of July Jam, also featuring Ne-yo, Jill Scott, J. Cole, Grace Potter, Ben Taylor and Hunter Hayes (in place of Demi Lovato), hosted by North Philly's own Kevin Hart.

Some Sirius celebs were in town to rock out to Mayer, including the Howard Stern Show's Jon Hein (who dined at Old City's Campos before the show). The event was hosted by Mark Goodman, who you may remember as an OG MTV VJ but now gets his paycheck from the Spectrum music channel on Sirius.

* The Roots' Questlove and Black Thought held a mini-performance outside South Street's TLA yesterday that will be filmed for VH1, which will simulcast the 4th of July Jam festivities. 6ABC will also carry the telecast.