REMOTE CONTROL OF THE SHIPS HORNS
Our idea was to create a piece of music that incorporated space and landscape directly into the composition, allowing the composer to use space in a new way, by using the reverberation of the landscape as a timbral element. Acoustic modeling and technical methods we developed for remotely controlling the ships horns, allowed for a musical performance where sounds originating miles away from the audience combined with more conventional instrumentation.
The technology allowed us to compensate for the speed of sound, so that sounds of ships’ horns arrived in time with musicians playing onshore. By defying our normal expectations of physics, the experience of hearing sounds from different distances, coming together in this way, was profoundly strange. Small computers equipped with radio links and GPS modules controlled the horns of vessels floating offshore, compensating for the time delay of the arriving sound so that even horns played several miles away could be heard in time with musicians on shore.
Vessels were equipped with a small computers capable of controlling the valve that activated the ship's horn. The controllers had GPS positioning capabilities and extremely accurate clocks that were synchronised by GPS satellites, so each controller had a precise base time signal that was perfectly synchronised with all of the other controllers and a master computer on shore. The GPS positioning capability of the controllers allowed them to determine their location and their distance from the audience, and therefore the amount of time it would take the sound of their horn to reach the ears of the listeners.
As the controllers played the horns automatically, ships crews didn't need any musical ability themselves - they only need to be able to move their vessels to their required positions. Prediction of the volume and timbral qualities of the ships horns was calculated using the ExSound2000 software from Delta Acoustics. This allowed us to predict the effects of different wind and atmospheric conditions on the sounds of the ships horns.