Organ playing 639-year-long composition changes chords for first time in years

An organ playing a 639-year-long experimental composition has finally changed chords after two painstaking years.

John Cage's piece titled As Slow As Possible began in 2001 and will live up to its name when it's completed by the year 2640.

The organ's first two years were spent in silence until it voiced its first note in 2003.

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Since then, it's been playing at Burchardi Church in Germany, where the chords change in either days, months or years.

Dozens of keen - and patient - music lovers gathered at the church yesterday to hear the rare chord change exactly two years on from the last.

A pipe was added to the organ to add a 'd' note to the chord in the piece's 16th chord change since it began.

The chord went from c' (16'), des'(16'), dis', e', ais', e'' to c' (16'), des'(16'), d', dis', e', ais', e''.

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Cage's piece is described as history-making and, once completed, will be the world's longest ever music composition.

The piece consists of eight parts which must be played and cannot be repeated. However, nothing is fixed except the pitch and the duration of the sounds.

A ceremony, therefore, accompanies each chord change.

The next chord change will be in another two years on August 5 2026 and sounds can be listened to here.