Kronos Quartet is a string quartet founded by violinist David Harrington in 1973. Since 1978, the quartet has been based in San Francisco, California. The longest-running combination of performers (1978–1999) had Harrington and John Sherba on violin, Hank Dutt on viola and Joan Jeanrenaud on cello. Jennifer Culp replaced Jeanrenaud on cello in 1999. Jeffrey Zeigler replaced Culp on cello in 2005.