The bass guitar of Bob Babbitt remains an indelible element of the famed Motown sound -- his melodic, jazz-inspired grooves propel dozens of the most memorable hits from soul's golden era, including Stevie Wonder's "Signed, Sealed, Delivered," Smokey Robinson & the Miracles' "The Tears of a Clown," Marvin Gaye's "Mercy Mercy Me," and Gladys Knight & the Pips' "Midnight Train to Georgia." Born Robert Kreiner in Pittsburgh, Babbitt studied classical music as a teen but soon gravitated to rhythm & blues, and by age 15 he was playing upright bass in a number of local bar bands. Upon first encountering an electric bass during a club date, the 17-year-old Babbitt traded in his upright for a 1960 Fender Jazz Bass guitar. From there he turned down a music scholarship and in 1961 relocated to Detroit, working construction jobs by day while moonlighting in area nightclubs. Within a year Babbitt signed on with the Detroit rock & roll band the Royaltones, scoring a series of regional hits including "Flamingo Express." The quintet ultimately captured the attention of Michigan-born star Del Shannon, who recruited them to serve as his backing unit -- the Royaltones remained with Shannon through 1965, cutting cross-Atlantic chart hits including "Little Town Flirt" and "Handy Man." Upon leaving the group, Babbitt emerged as an in-demand Detroit session player, becoming a fixture at Motown rival Golden World Studios, where he played on hits like Edwin Starr's "Agent Double-O-Soul," the Capitols' "Cool Jerk," and Darrell Banks' monumental "Open the Door to Your Heart."