CD

The Essential Bill Monroe and His Blue Grass Boys, 1945-1948 (Sony, two CDs). Bluegrass took shape in these classic recordings, the best of which also feature Lester Flatt on guitar and lead vocals and Earl Scruggs on banjo–a supergroup by any conceivable standard. Listen first to “It’s Mighty Dark to Travel” and you’ll hear in three electrifying minutes exactly what Monroe and his colleagues contributed to the history of American music (TT).