John Cage Organ Organ²/ASLSP Halberstadt

What does 639 years sound like?

In 1985, the American composer John Cage wrote a piano piece whose title later became his inspiration: ORGAN²/ASLSP — As Slow As Possible. How slow is 'as slow as possible'? In Halberstadt, an international team of artists has been performing a piece since September 5, 2001, that is scheduled to last 639 years. The piece is played on a specially built organ in the Burchardi Monastery — and, if everything goes according to plan, will end on September 5, 2640.

Klangwechsel as a global pilgrimage destination

Every time a new tone is added or an existing one is removed, a Klangwechsel takes place. These changes are the only 'concerts' in the classical sense: hundreds, sometimes over a thousand people travel from all over the world to witness the moment when an organ stop is changed. The Klangwechsel have become an international phenomenon since 2001, mobilizing the intersection of contemporary art, philosophy, and religion.

The 17th Klangwechsel — August 5, 2026

In 2026, the 17th Klangwechsel will be celebrated on August 5, 2026, at the Burchardi Monastery in Halberstadt. After 25 years of continuous performance, the piece is only about 4% complete. The project operates without state funding — it is financed exclusively through private donations, sponsorships (639 are permanently visible in the church), art purchases, and the famous 'Final Ticket': a ticket for the final event in the year 2640, which can be purchased today and inherited.

Halberstadt in the state of Saxony-Anhalt

Halberstadt is located in the Harz district in the state of Saxony-Anhalt. The city is a bishop's seat, has significant Romanesque-Gothic architectural history (Halberstadt Cathedral, Church of Our Lady, Burchardi Monastery), and in recent years has developed an unexpected profile as a location for the most experimental contemporary sound art. The John Cage Organ Project is now one of the most famous cultural landmarks in Saxony-Anhalt, attracting visitors from Tokyo, New York, and São Paulo to Halberstadt.