“I’ve grown accustomed to the road, and know how to stay out there without getting all bombed out or doing damage to my health,” says 69-year-old country-blues guitarist John Cephas. For 23 years the Paige, Va., resident and his 45-year-old harmonica-playing Takoma Park partner, Phil Wiggins, have been rural American music’s emissaries to the world, playing nearly every continent as Cephas & Wiggins. In support of their new album Homemadetheir 10thon Chicago’s Alligator Records, Cephas & Wiggins will be touring Switzerland and Germany. (They appeared locally on April 10 at Harmony Hall in Fort Washington.) On Homemade, Cephas & Wiggins make standard blues themesmy-woman-left-me in “Leaving Blues,” I’m-broke-but-still-feeling-fine in “A Lot of Them Blues”sound fresh. “We’re always looking for new material,” says Cephas, and on Homemade, they nicely mix originals with covers by the likes of Skip James, Memphis Minnie, and the Rev. Gary Davis.