A musician himself, Severinsen was a master jazz trumpeter. In his early career he toured with Tommy Dorsey, Benny Goodman and more. After the war, he landed a job at NBC as a studio musician where he accompanied Steve Allen, Eddie Fisher and Dinah Shore. In 1962 he was asked to join the musical team for the Tonight Show starring Johnny Carson. He went onto become band leader and fill in host for Carson. He continued for the next 30 years in this role until Carson’s retirement.