As a special (but not entirely unexpected) surprise vocalist Cedric Bixler-Zavala joined guitar player Omar Rodriguez-Lopez for the entirety of his announced set, essentially making this a set from The Mars Volta. Pure jammy fun, Rodriguez-Lopez is still one of the best working guitar players. The group, played to the ebb-and-tide dynamics of jam rock without sliding into wonky Phish territory. Sadly though, the first half of the set found the namesake performer’s guitar drowned in the mix. Better question: why not just have had The Mars Volta play?