In 2005, the English Folk Dance and Song Society asked sound sculptor Henry Dagg to create a few interactive pieces for the gardens of London's Cecil Sharp House. They gave him six months and about $90,000 to complete the project and pretty much nothing went according to plan.
It ended up taking Dagg five years and closer to $150,000 to build one large, solar powered music box that played itself, and couldn't be kept in an outdoor garden, as was originally intended. Ultimately, he decided to buy himself out of the original agreement with the English Folk Dance and Song Society and kept his 'Sharpsichord' for other ventures.
Here's how Dagg's remarkable music box works:
The Sharpsichord is an automatic acoustic harp, which is designed to allow any musician to compose his or her own music by screwing a 'pin' into the surface of a perforated cylinder at the position required for each note to be played. Each of the 11, 520 holes is threaded to accept one of the 3mm threaded pins kept in a tray under the cylinder. A scale across the top shows the pin position for every note in the 46-note chromatic scale, while another scale at the side calibrates time by numbering each of the 240 horizontal lines of of holes. As the cylinder rotates, each pin lifts a lever coupled to a mechanism, which plucks the appropriate string. Each pair of strings transfers its energy to a rocking bridge coupled to a long diaphragm whose vibrations are amplified acoustically by a large horn at the bass end, and a smaller horn at the treble end. A keyboard allows real-time performance and helps note finding. The solar panels can charge the battery, which runs the motor.
This special instrument was built entirely out of stainless steel and has one very obvious design flaw: The cylinder only holds from 40-90 seconds of new music before it begins to repeat. However, this didn't stop Bjork from including the 'Sharpsichord' in her 2011 'Biophilia' tour. Don't miss the guided tour of Dagg's pin-barrel harp in the video.