 He completed his studies at the Belgrade Academy of Music under Bruno Brun, and then studied at the Paris Conservatory under Ulysse Delécluse.Ačkun gave concerts as a soloist in nearly all great towns in Yugoslavia, as well as in France, West Germany, Austria, Italy and Bulgaria, playing under the leadership of such conductors as Zubin Mehta, Jean Martinon, Charles Bruck, Krešimir Baranović, Oskar Danon, Milan Horvat, Živojin Zdravković.Distinguished Yugoslav composers, such as Stjepan Šulek and Zlatan Vauda, dedicated their compositions to him.