From intricate jazz solos to his "Concerto for Diatonic Harmonica and Orchestra,” he has stretched the harmonica beyond its ostensible limits. She sings “old modal folk songs” with Solas one week and performs with the indie band tUnE-yArDs the next. This week, "Musician's Spotlight" features encores with Howard Levy and Moira Smiley , two musicians for whom visionary boundary-pushing is just an ordinary Tuesday.