One of the most fascinating personalities in the contemporary classical music scene is the Canadian Barbara Hannigan, who is equally outstanding as a singer and conductor and an unflinching pioneer in terms of concert presentation. The vocal part in Arnold Schönberg's legendary String Quartet op. 10 from 1908, which opened the door to atonality in a very romantic, immediately captivating way, is as if made for Hannigan's spherically clear soprano. "I feel air from another planet": Stefan George's verses, which Schönberg set to music so brilliantly, describe the feeling of harmonic weightlessness that Mozart created in the exceptionally bold introduction to his Dissonances Quartet. When the Belcea Quartet, one of the best ensembles ever, sits on the podium, as it does here, the demanding expedition becomes a pure pleasure.