The most interesting acoustic features are flutter echoes between the buildings bordering the space. One zone of flutter echo is between the buildings marked A and B in figure 1. Another is in the corner marked C. However, these acoustics tend to go unnoticed unless inputting loud transient sounds (e.g. clapping, shouting or the bang of a car door), or by standing in specific locations and talking or making sound at a normal volume. The calls of crows and seagulls flying overhead also stimulate these acoustic features combined with a general reverberation of the area.
The acoustics are clearer in the winter when there is less vegetation to dampen the sound.
By recording 3D impulse responses it would then be possible to emphasise their presence through sound processing in composition, and then project these reflections over the loudspeaker array. For more information on this process, see the page on impulse responses.
3. Ambisonics loudspeaker array
Two different approaches to the loudspeaker array were tested: (a) a layout that used the hedges for disguise, where one speaker was necessarily prominent at the front due to cabling and public safety. This setup was a surrounding array over which ambisonics could be decoded, (b) a distributed array where loudspeakers were used as mono sources creating both direct and reflected sound. The former was found to be most interesting in the given context due to reduced visual impact and the ability to project a new, complete sound-field, layered into the real sound-field. The location of the loudspeakers are shown in red on figure 2. The photos below show some of the loudspeakers in the hedges.
