In 1988, Sieuwert Verster and Ad ’s-Gravesande produced the documentary “Het orkest, geluid van een eeuw” (The Orchestra: Sound of a Century) for Dutch broadcaster VPRO, marking the Royal Concertgebouw Orchestra’s centenary that same year. In preparation for the film, Sieuwert Verster conducted numerous interviews with current and former orchestra members and others associated with the Concertgebouw Orchestra.

Several years after the documentary was completed, producer Sieuwert Verster donated the raw footage, which is often destroyed after production, to the Netherlands Music Institute. Much of this footage was not used in the final documentary. The segments of these interviews concerning conductor Willem Mengelberg are available via the Willem Mengelberg Society’s website, as well as on YouTube.

Willem Mengelberg’s biographer, Frits Zwart, developed the concept. Financial support from the Willem Mengelberg Stiftung (Switzerland) enabled the digitization and editing of the audio and visual material.

To ensure wide accessibility, the interviews have been subtitled in English.