Björn Hallman, Cecilie Løken Hesselberg, Karl Frisendahl Björn Hallman is a composer, conductor, and musician (piano, viola and flute). Hallman was a conductor at the Stockholm Royal Opera from 1972 to 1997 and is frequently invited as a guest conductor in orchestras in Sweden and internationally. Since the 1980s, Björn Hallman has made a name for himself as a composer of wide-ranging accomplishments. His catalogue of works includes some 200 hundred compositions ranging from chamber music, opera and ballet to musical and film music.