Charles Edward Haden was an American jazz double bass player, bandleader, composer and educator whose career spanned more than 50 years. Building on the work of predecessors such as Jimmy Blanton and Charles Mingus, Haden helped to revolutionize the harmonic concept of bass playing in jazz, evolving a style that sometimes complemented the soloist, and other times moved independently, liberating bassists from a strictly accompanying role, to allow more direct participation in group improvisation.

James Blanton was an American jazz double bassist. Blanton is credited with being the originator of more complex pizzicato and arco bass solos in a jazz context than previous bassists. Nicknamed "Jimmie," Blanton's nickname is usually misspelled as "Jimmy," including by Duke Ellington.