Exciting audiences as instrumentalists, singers, even as dancers, while digging further into the broad legacy of Southern music, particularly African-American Southern music, the group--a core trio of Mr. Flemons, Rhiannon Giddens and Hubby Jenkins (who recently replaced the departing third founder, Justin Robinson) and an array of additional contributors--have defied genre classification by charging, fully prepared, into many fields. The Carolina Chocolate Drops' last release, 2010's "Genuine Negro Jig," won the Grammy for Best Traditional Folk Album, but they have also been featured at the Newport Jazz Festival, on the Grand Ole Opry and in rock clubs; they have topped the bluegrass charts, and have been referred to as an Americana jug band, an old-timey African-American string band and even as an R&B group.

Mr. Flemons, a showman who handles guitar, jug, harmonica and bones for the band, started out as a more conventional roots-rock and pop musician. Ms. Giddens, the group's stunning, soulful vocalist and banjo and fiddle player, was classically trained. They, along with Mr. Robinson, the former Chocolate Drop multi-instrumentalist, were in their 20s when they met at the Black Banjo Gathering, an annual get-together in Boone, N.C., for those interested in reviving the African-American stringband tradition.

They went on to study under and perform with Joe Thompson, who was considered--before his death last month at age 93--the last of the great fiddlers left playing that generations-old music. (One of Thompson's instrumentals, "Riro's House," leads the new CD.) While rural stringband music was a large part of the Chocolate Drops' initial focus--and its newcomer, Mr. Jenkins, is also a banjoist--the band's interest in reviving older music and performance styles for contemporary audiences was never limited to solemn turns on traditionalist folk styles. The more exuberant parts of the musical spectrum--hokum blues, jazz, vaudeville--were always included in the music they chose to bring forward, which has ranged from a turn on 1920s banjoist Papa Charlie Jackson's "Your Baby Ain't Sweet Like Mine" to Ms. Giddens's soulful, always show-stopping version of 1990s R&B singer Blu Cantrell's "Hit'em Up Style."

Fresh off a recent win at the 53rd annual Grammy Awards, The Carolina Chocolate Drops make their second appearance on Mountain Stage. The band modifies and preserves the traditional fiddle and banjo music of the Piedmont, recently adding two new members -- multi-instrumentalist Hubby Jenkins and beatboxer Adam Matta -- to its continually evolving sound.

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