His most important opera, I dispettosi amanti (The Lovers' Quarrel), received its premiere at the Metropolitan Opera House, Philadelphia, in March 1912. In 1925 Parelli returned to Italy and became artistic director of the newly formed Unione Radiofonica Italiana (Italian Radio Union; now RAI) in Milan. In 1926, I dispettosi amanti became the first opera to be broadcast in its entirety on Italian radio.[2][3]
Parelli married his student Isolina Rapalli. They had no children. He died in Monteleone d'Orvieto on 26 December 1944 and lies buried in the cemetery of his native village.[1]