Composer John Cage. Photograph: Julia Malakie/AP
Its organisers call it the longest concert in the world. Almost seven years in, and with 632 years left, it is unlikely anyone will challenge the claim. On Saturday a performance by the late avant-garde American composer John Cage inched to its sixth chord change since it began in the medieval church of St Burchardi in the German town of Halberstadt in Saxony Anhalt in September 2001.
"ORGAN2/ASLSP As Slow aS Possible", a 4.07 metre-long score which would stretch to an estimated 47,000 kilometres in its elongated form, originally took a mere 29 minutes and 15 seconds to perform when it was premiered in 1987. Believe it or not, it has become one of the most talked about events of the German cultural calendar. The weekend's change to C4-A flat4 which happened at precisely 3.33pm, attracted about 1,000 spectators including Cage fans.
The church has been forced to erect a Perspex sound barrier outside after complaints from neighbours who say the tone which plays uninterrupted until the next change, was hard to bear. There have been periods of silence - for instance an 18-month pause until February 5 2003 - which came as a welcome relief to some.
Those who missed the latest event may journey to Halberstadt on November 4 2008, when a further tone change is to sound. And in several years' time, one note will sound for 58 years without a break - organ specialists will be on hand to ensure the organ is robust enough to handle the strain.
The town was chosen to host the concert because it was here in 1361 that the world got its first large organ, which had a huge influence on the development of the church organ around the globe.
Over this century the organ is to be expanded, financed by sponsorship of the sounds. A single "year of sound" will cost €1,000 and in return the donor's name will be added to a plaque on the wall of the church.
It is a fascinating study in time and music which challenges our concept of slowness. The hope is to establish a creative continuum over generations. Organisers say only war or a rebellion against creativity and art will be able to halt the concert's progress.
