Born in Arezzo, at 18 years old Boncompagni moved to Sweden, where he lived for ten years doing various jobs, graduating at the Swedish Academy of graphics and photography and starting a radio career as a disc jockey. Married to a Swedish woman, after divorcing in the early 1960s he moved back to Italy with his three daughters, and together with Renzo Arbore he created the radio program Bandiera gialla, the first Italian musical program focused on rock music and other avantgarde genres. In 1970 the duo Arbore-Boncompagni also created Alto Gradimento, an innovative and successful radio variety show which launched the career of several comedians, including the brothers Franco and Giorgio Bracardi.