John Cage’s 639-Year Organ Piece Just Changed Chords — Here’s What Happened on August 5, 2026

What Changed and Why It Matters

The chord shifted from 7 notes to 8 notes, with an A4 pipe being added to the mechanical organ . This was the 17th chord change since the performance began, and the first change in about 2.5 years — the previous change occurred on February 5, 2024 .

This event marked roughly 4% completion of the full 639-year performance . The composition is scheduled to finish on September 4, 2640 .

How the Performance Began — and When It Will End

The performance began on September 5, 2001, with a silent rest that preceded the first note, which was sustained from February 5, 2003 onward . The piece is being performed in the former Cistercian convent church of St. Burchardi in Halberstadt, Germany .

How the Organ Sustains Sound Between Changes

The organ is a purpose-built mechanical organ with pipes that remain open continuously, sustained by electric blowers that feed air to the pipes without interruption . No human performer is present — the organ holds each chord indefinitely via its mechanical and electrical systems. The chord that sounded from February 2024 until August 2026 consisted of seven notes .

When Is the Next Chord Change?

The next (18th) chord change is scheduled for October 5, 2027, when a note will be removed, shifting from 8 notes back to 7 . Specifically, the E4 pipe — previously added on September 5, 2020 — will be released . According to the project's official Wikipedia entry, chord changes are planned well into the future, with the 19th change scheduled for April 5, 2028 .

A Performance That Redefines Patience

John Cage's "ORGAN²/ASLSP" is an avant-garde composition that instructs performers to play "as slow as possible." The Halberstadt interpretation — lasting 639 years — was inspired by the fact that the Halberstadt cathedral housed one of the first organs ever built around 1361 . Each Klangwechsel (sound change) has become an international pilgrimage destination, and premium tickets for the 17th change required a €200 donation . The project even offers a "Final Ticket" for those who want to reserve a seat for the end in 2640 .