The addition of an E and E-sharp complement the G-sharp, B and G-sharp that have been playing since February 2003 in composer John Cage’s ‘Organ2/ASLSP’ or ‘Organ squared/As slow as possible.’
The five notes are the initial sounds played on a specially built organ – one in which keys are held down by weights, and new organ pipes will be added as needed as the piece is stretched out to last generations.
The concert is more than just an avant-garde riff on Cage’s already avant-garde oeuvre, which includes a piece consisting of 4 minutes and 33 seconds of silence and one for a piano rejiggered with screws and wood stuck between the strings.
The concert began Sept. 5, 2001 – the day Cage would have turned 89. The composition, originally written to last 20 minutes, starts with a silence, and the only sound for a first 1 1/2 years was air. The first notes were played in February 2003.
After debates in Germany about what exactly ‘as slow as possible’ could mean – anywhere from a day to stretching on infinitely – the group of German music experts and organ builder behind the project chose the concert’s 639-year running time to commemorate to the creation of the city’s historic Blockwerk organ in 1361.

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