"Beneath the ballroom" sounds like the setting of an unsolved mystery, but it's really the location of on of the city’s newest music venues. Social Hall SF opened directly below the classic Regency Ballroom, auspiciously kicking off with a show headlined by Neon Indian. Formerly a space for private events or Regency Ballroom overflow, the 600-capacity venue’s low ceiling and underground atmosphere will lend itself to indie music, DJ performances, stand-up comedy, EDM shows and punk music.