[2] In February 1964 he completed post-graduate courses in Paris at the Conservatoire National Supérieur de Musique, where he studied with Nadia Boulanger, Manuel Rosenthal and Olivier Messiaen.

Between 1998 and 2000, Emil Simon was also the artistic director of the Transylvania State Philharmonic Orchestra of Cluj Emil Simon had a wide-ranging repertoire of symphonic works of all periods and styles,[4] and he was a promoter of symphonic music written by Romanian composers, like George Enescu,[5] Sigismund Toduta, Cornel Țăranu, Liviu Glodeanu, Mihai Moldovan, and Tiberiu Olah, among others.

Many of these pieces were recorded in Romania for broadcast on radio and television, as well as on LPs and CDs, primarily for the Electrecord label.

In his role as a teacher, he participated in the formation of new generations of Romanian musicians by teaching the Orchestra and Chamber Music classes at the "Gheorghe Dima" Conservatory.

Simon was also invited to be a judge in international competitions in Italy, Germany, Hungary, and he taught master classes at various universities.