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A style of American country music that grew in the 1940s from the music of Bill Monroe and his group, the Blue Grass Boys. It combines elements of dance, home entertainment and religious folk music of the rural South-east. A bluegrass band typically consists of four to seven individuals who sing and accompany themselves on acoustic string instruments: two rhythm instruments (guitar and double bass) and several melody instruments (fiddle, five-string banjo, mandolin, steel guitar and second guitar). Lead instrumentalists take solo breaks between verses of a song and provide a harmonic and rhythmic background often in a responsorial relationship to the vocal part. Instrumental works have alternating solos as in jazz...The vocal range of bluegrass music is higher than most country music singing...The music is mostly in duple meter with emphasis on the offbeats...Tempos are generally fast...
Source: Grove Music Online
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