In 1971 Soltész started his career at the Theater an der Wien. In the following two decades he was conductor of the Vienna State Opera, the Hamburg State Opera and then the Deutsche Oper in Berlin. From 1992 to 1997 he was conductor at the Flemish Opera in Antwerp and Ghent. In 1997 he was appointed artistic director and music director of the Aalto Muziektheater in Essen. Under his leadership, it acquired great international fame and appreciation. He held that position until 2013.
Soltész has also conducted in many of the other major European opera houses, including those of Frankfurt, Rome, Budapest, Warsaw, Moscow and Paris.