Concert

From 1994, Chum has appeared in concerts successfully. He has sung the tenor parts in Bach's Christmas Oratorio, St John Passion and St Matthew Passion, in Handel oratorios, Beethoven's Ninth Symphony, and work by Mendelssohn, among others, with the Gewandhausorchester in Leipzig conducted by Riccardo Chailly.^[1] At the Gewandhaus in Leipzig, he also sang Schubert's Winterreise in the orchestral version by Hans Zender.^[1]

Chum has also worked with conductors including Sylvain Cambreling, Dennis Russell Davies, Christopher Hogwood, René Jacobs, Fabio Luisi, Sir Charles Mackerras, Ingo Metzmacher, Sir Roger Norrington, Jordi Savall, Peter Schreier and Bruno Weil.^[1]

Opera

Chum made his operatic debut at the Landestheater Niederösterreich as Lysander in Britten's A Midsummer Night's Dream.^[2] He focused on Mozart roles, such as Belmonte in Die Entführung aus dem Serail, Tamino in Die Zauberflöte, Ottavio in Don Giovanni, and the title role in La clemenza di Tito.^[1]

He was recognized internationally in 1998 performing the title role of Mozart's Idomeneo at the Landestheater Salzburg.^[1] At the Burgenland Haydn-Festspiele [de], he appeared as Germando in L'isola disabitata in 1998 and Rinaldo in Haydn's Armida in 1999. He performed as Nerone in Monteverdi's L'incoronazione di Poppea at the Oper Frankfurt.^[2]

From 2000, the singer worked at the Komische Oper Berlin with director Harry Kupfer for many years. He performed the Mozart roles of Tamino, Titus, Ferrando and Don Ottavio, Romeo in Gounod's Roméo et Juliette, and Piquillo in Offenbach's La Périchole.^[1] At the Theater an der Wien, Chum appeared among others in 2008 as Kudrjaš in Janáček's Katja Kabanowa, in 2009 as Graf Hohenzollern in Henze's Der Prinz von Homburg,^[1] and in 2013 as Jaquino in Nikolaus Harnoncourt's Fidelio production. In 2013, he also sang two tenor roles there in a concert performance of Viktor Ullmann's chamber opera Der Kaiser von Atlantis. In Graz, he performed the title role in Offenbach's Barbe-bleue, and for the first time the title role of Wagner's Lohengrin.^[1]