On 11 September, Arvo Pärt’s 80th birthday, Helga Davis presents Toomas Siitan’s 24-hour playlist A World Apärt, a programme that originally streamed on 24 September 2014.

This year, the marathon will culminate with a live webcast of the New Juilliard Ensemble performing chamber works at the Metropolitan Museum of Art’s Temple of Dendur. Among the works performed will be Fratres, Spiegel im Spiegel and Wallfahrtslied.

Listen to the programme on Q2 Music