Robert Bradley's Blackwater Surprise, with John McEuen and Jimmy Ibbotson, Sunday, March 19, as part of an E-Town taping at the Boulder Theater, has maintained a somewhat more than normal level of interest in the past few years, based as much on the mythology of the band's formation as on its self-titled debut, released in 1996. The story goes like this: The future members of the Surprise were hanging out in a recording studio when they heard Bradley busking soulfully below on a Detroit sidewalk. They invited the blind vocalist up, jammed with him, and soon began recording music that mated Bradley's Motownesque vocal stylings with the foursome's funk-and-rock sensibilities. On its new album, Time to Discover, the band sounds even groovier, even down-and-dirtier than before, employing electric pianos, B-3 organs, and a little disciplined wah-wah and church-choir backing vocals that elevate the Otis Redding-like reach of Bradley's voice. Attempting to fuse gospel, blues, Superfly, the Stones, the Black Crowes, and even white-boy rap (fellow Motor City dweller Kid Rock lends a restrained refrain to the album's opening track) is an endeavor that could easily skirt the overblown or excessive. The real surprise here, though, is that it works.