Beethoven X

To mark the 250th anniversary of Beethoven's birth, Deutsche Telekom commissioned a team of musicologists, music historians, and computer scientists to create a realisation of his 10th symphony from the fragmentary sketches he left behind. The team collaborated for two years, from 2019 to 2021, to research and develop artificial intelligence algorithms, data collection methodologies, and human–artificial intelligence (AI) collaborative strategies to achieve this ambitious goal. The project involved the use of then-emerging large language models (LLMs) to develop the symphony from Beethoven's sketches. Alongside the technological development, the project focused on exploring and establishing an interactive paradigm of collaborative creativity between human experts and AI. The project's culmination took place in October 2021 when the Beethoven Symphony Orchestra performed the completed work in a live event in Bonn, his birthplace, which was broadcasted worldwide. This collaborative endeavour, affectionately dubbed “Beethoven X”, garnered global media attention and received several awards. This book chapter documents the journey of the Beethoven X project, highlighting the challenges and insights that emerged from establishing novel methodologies for creative collaboration between human experts and emerging AI technologies. It also examines the public and expert reception of the work and the debates it sparked about creative values, authenticity, and creative agency.