He conducted the Royal Romanian Opera on tour when aged only 15, and then held many important appointments as operatic conductor, beginning with Düsseldorf Opera, 1928-1932 (when aged 18 to 23). Then he was at Brno (1932-1935), Bern (1935-1945) and Vienna, with much travelling and concert-giving all over Europe, and recordings made with the Vienna Philharmonic, the Netherlands Philharmonic and the Zurich Tonhalle Orchestra. He held Swiss citizenship.