After studying saxophone privately, Kelso joined a Los Angeles dance band when he was 15. Through the 40s he played with dance bands, in a US Navy band while on military service, and with many leading names in the jazz world, including Benny Carter, Benny Goodman, Lionel Hampton, Kid Ory and Lucky Thompson. For two decades from the mid-60s, Kelso was a studio musician but took time off for tours with Hampton and for many years could be heard gigging with leaders, mainly of big bands, such as Ray Anthony, Bill Berry, Duke Ellington, Gene Harris, Johnny Otis, Frank Capp and Nat Pierce’s Juggernaut, Billy Vaughn and others.



After the mid-80s, Kelso became semi-retired but was occasionally heard playing with bands led by Berry and Harris, and the ongoing Count Basie Band. A solid section player, Kelso was adept on several instruments of the saxophone family as well as flute and clarinet. He was also an inventive and driving soloist. From the late 90s, he used the original spelling of his surname.