4 March 2022, Cool Logic, Bas Cornelissen

Arvo Pärt is one of the most popular contemporary composers. In fact, according to one count, he was the most performed contemporary composer in eight successive years from 2011 to 2018. Who would have expected that from algorithmically composed music? Indeed, that is how Pärt arguably composes: his style, known as tintanibulli, heavily relies on the use of simple mathematical procedures. They can regulate everything from the structure of a piece to the duration of individual notes. To better understand that process, we analyze and formalize Pärt's composition Summa. The algorithm we implement almost completely reconstructs the work: it outputs a musical score that matches the original in over 93% of the notes. In fact, as a result of dependencies between the notes, only 3.5% of the notes really remains to be corrected. Our work not only demonstrates that Pärt's approach to composition is deeply formal, it also invites new algorithmic compositions in his style.