Who hasn’t wanted a blues name? These evocative monikers mark you as a member of that hippest of castes: the hard-knocked, dues-paid artist—and it can only be a matter of time before blues aficionado Tim Duffy gets his. Duffy’s the director of the Music Maker Relief Foundation, an organization that gives direct aid to aging players of this aged genre. The organization’s upcoming DVD series, “Drink House to Church House,” profiles several of these musicians—most of them virtual unknowns—with richly detailed performance and interview footage. Their words, however, are often as meaningful as their songs: Of the music Duffy and the rest of these folks have given their lives to, Alabama Slim says, “It’s like a can opener that’s pryin’ in your heart.” Call yourself “Groovin’ Benefactor” when clips from the series show at 8:30 p.m. at the Avalon Theatre, 5612 Connecticut Ave. NW. Free (donations accepted). (202) 966-6000. (Pamela Murray Winters)