Music Worcester brings Sam Bush, known as “The King of Newgrass” and his revolutionary take on bluegrass to Worcester’s Hanover Theatre on June 9. The mandolin/fiddle/guitar-playing icon has taken the genre to new heights over a 50+ year career as a founding member of The New Grass Revival, and working with such legends as Leon Russell, Emmylou Harris, Lyle Lovett, and Béla Fleck & The Flecktones.