He then performed as a tenor opera singer in Bayreuth, Berlin, Budapest, Buenos Aires, The Hague, Frankfurt/Main, Cologne, Leipzig, Munich, Paris, Salzburg and Vienna.
At the world premiere of Delius' opera in 11 pictures Fennimore and Gerda[9] he sang in 1919 alongside John Gläser, Emma Holt and Elisabeth Kandt.
Examples of his appearance in modern operettas are Madame Pompadour by Leo Fall, where he sang René, Comte D'estrades, and Münchhausen[10] by Ernst Steffan[11] where he could be heard in the premiere on 23 December 1927 alongside Hella Kürty, Rose Ader and Fritz Schulz.
At the end of the 1920s, Wirl's participation in performances of contemporary musical avant-garde such as Paul Hindemith's lustiger Oper in drei Teilen[12] Neues vom Tage and Lindberghflug[13] cf.
"One of the most legendary plays from the late 1920s is a cooperation of Kurt Weill and Paul Hindemith on a text by Bert Brecht..." and in the record studio.