The bass baritone, Robert Koller, has many years of experience in the concert and opera world. He has performed in prestigious opera houses and concert halls such as "Alte Oper Frankfurt", Zellerbach Hall/San Franciso, Semperoper Dresden, Philharmonie Berlin and the Teatro Colon in Buenos Aires, under various conductors like Andrea Marcon, Heinz Holliger, Zsolt Hamar, Emilio Pomárico and Jordi Savall.
Since 2004, he has been singing the role of King Cosroe in "Siroe, Re di Persia" by Haendel with the Venice Baroque Orchestra, under the direction of Andrea Marcon at the Musikhalle Hamburg and at the Zellerbach Hall, San Francisco. This has led to his soloist appearances in various works by Charpentier with the Capella Reial de Catalunya under Jordi Savall at the Styriarte Graz, the festival of Ambronay and the Basilica of Vézelay.
He has performed a broad range of leading roles and recitals in renowned theatres and festivals including the Società di Quartetto Milano, the Summer Concerts of the Audi-Forum Ingolstadt, the Teatro Principal de Guanajuato as part of the Cervantino Festival Mexico, the Ruhr-Triennale, the Festival of Montepulciano, the Davos-Festival, the Gaida Festival Vilnius and the Lucerne Festival with the Lucerne Festival Strings at the KKL.
Swiss radio broadcasted his solo performances with leading Swiss orchestras such as the Orchestre de Chambre de Lausanne, the Kammerorchester Basel, the Kollegium Musicum Winterthur, the Basel Sinfonietta (at the Stadtcasino Basel), the Ensemble Phoenix or the Contrechamps Genève.
He was the leading role in "Extravagancia" at the Teatro Colón in Buenos Aires in 2010 (staged by Rafael Spregelburd), and in "Nacht" by G.-F. Haas at the Lucerne Festival (KKL) in 2011.
Semperoper Dresden employed him the following year to sing the title role in "El Cimarron" by H.-W. Henze.
2013 brought him further soloist engagements at the "Ittinger Pfingsttage" conducted by Heinz Holliger, at the Grande Opéra de Genève with Kurtàgs' "pas à pas..." and at the Wiener Musikverein to sing the bass solo in "Missa Solemnis" by Beethoven.
Since 2014, Robert has been working under Heinz Holliger for the baritone song cycle "Lunea" at the Alte Oper Frankfurt (world premiere of the orchestrated version by Holliger) with the Ensemble Modern, which was broadcast by Radio Hessen (hr2). In the same year, he sang the baritone solo in "Dunkle Spiegel" conducted by Heinz Holliger at the Tonhalle Zürich.
In 2015, Robert will appear with the baritone song cycle "del aram" with the Brandenburgisches Staatsorchester, as well as a soloist in Beethoven's Ninth at the Berliner Philharmonie and at the Aichi Arts Center at Nagoya. In autumn there will be further solo performances with Heinz Holliger at the Tonhalle Zurich, and with Emilio Pomárico at the Alte Oper Frankfurt.
In 2016, he performed the solo parts of "Walpurgisnacht" by Mendelssohn with the Tonhalle Orchester Zürich at the Tonhalle Zürich.
The recommendation of Kaija Saariaho lead him for the solo part in "Sombre" both at Njord Biennale in Copenhagen and at Schwetzinger SWR Festspiele 2016.
At the Lucerne Festival 2016 he was the leading role of the opera premiere "Die künstliche Mutter" and soloist at the 2016 concert series of the BBVA Foundation at Bilbao.
In 2007, he sings the baritone lead part in the first performance of "musica profana" (Kelterborn) in Basle conducted by Heinz Holliger, the leading part of Luther in "Luther's dreams" with the Brandenburgisches Staatsorchester, as well as the lead baritone part in "Vikarë" in the opera house of Kraków, the leading role in the Opera "Dust" (European Culture Capital, Aarhus) and the baritone solo part in "Danse des morts" (Arthur Honegger) with the Basler Kammerorchester.
In 2018, he will be the baritone soloist with the Basle Symphony Orchestra in various pieces by Schumann, Mendelssohn and Bruch.