MANSFIELD -- When there are speakers hanging over the concourse and up on the lawn you know someone from Pink Floyd must be playing the Tweeter Center. Roger Waters, former bassist and songwriter for the legendary rockers, brought the surround sound, an unimpeachable nine-person band, and grand visual accompaniment to bear on a catalog steeped in majesty, misanthropy, and the tiniest glimmer of hope. In the first of a two-night stand Waters, looking fighting-trim, played a wide-ranging 2-hour-and-40-minute set with the celebrated 1973 Floyd album ``The Dark Side of the Moon" at its heart.