John Cage's 639-year organ performance reaches 17th chord change

The longest musical performance in the world, an organ rendition of John Cage’s "ORGAN²/ASLSP" (As Slow as Possible), has undergone its 17th chord change at the Burchardi Church in Halberstadt, Germany. The addition of a new A4 pipe increases the number of sounding notes from seven to eight, marking a significant milestone in a project that began on September 5, 2001. While the project spans a total of 639 years and is scheduled to conclude on September 4, 2640, the current progression represents only about 4% of the complete work.

The performance, which is managed by the John Cage Organ Project, maintains an extremely slow tempo where individual chords can last for years. The previous chord change occurred in February 2024, reflecting the deliberate, meditative nature of the composition. The project originally faced a long period of silence before the first notes were heard in February 2003, honoring Cage's directive to play the piece as slowly as possible.

Following this 17th chord change, the next adjustment to the composition is currently scheduled for October 5, 2027. Visitors and musicians continue to monitor the performance at the medieval church, which serves as a permanent site for this centuries-long cultural endeavor.