The UNVEILED PRESENCE (secret sounds 4) project makes use of the sound library of laser Doppler vibrometer recordings made in Helsinki in May 2010. In so doing, primarily mechanical vibration recordings of glass objects and thermally sensitive metal surfaces in the public urban space were used in a multichannel composition. The solid object sounds are projected in all directions of the space by means of a doubled 16-channel omnidirectional loudspeaker system. The space is filled with an adjusted mixture of direct sound and reflections, resulting in a virtual body of sound. The recorded vibration space, created in a solid object, is transformed into airborne sound, enclosing the recipient acoustically in the space. The granular details of the composition are consolidated in groups and change position on the cylinder loudspeakers at various speeds thus continuously altering the spatial effect. The loudspeaker systems hanging from the ceiling are encased in light-refracting plastic crystal chains and visually transform the spatial effect depending on the changing daylight.
