Peripheral interaction is a new approach to conveying information at the periphery of human attention in which sound is so far largely underrepresented. We report on two experiments that explore the concept of sonifying information by adding virtual reverberation to real-world room acoustics. First, to establish proof of concept, we used the consumption of electricity in a kitchen to control its reverberation in real time. The results of a second, in-home experiment showed that at least three levels of information can be conveyed to the listeners with this technique without disturbing a main task being performed simultaneously. This number may be increased for sonifications that are less critical.

The quote from Pierre Boulez, given as an epigraph to this article, inspired French researchers to start developing technology for spherical loudspeaker arrays in the 1990s. The hope was to retain the naturalness of sound sources. Now, a few decades later, one might be able to show that even more can be done: In electroacoustic music, using the icosahedral loudspeaker array called IKO seems to enable spatial gestures that enrich alien sounds with a tangible acoustic naturalness. After a brief discussion of directivity-based composition in computer music, the first part of the article describes the technical background of the IKO, its usage in a digital audio workstation, and psychoacoustic evidence regarding the auditory objects the IKO produces. The second part deals with acoustic equations of spherical beamforming, how the IKO's loudspeakers are controlled correspondingly, how we deal with excursion limits, and the resulting beam patterns generated by the IKO.

The icosahedral loudspeaker (IKO) is able to project strongly focused sound beams into arbitrary directions. Incorporating artistic experience and psychoacoustic research, this article presents three listening experiments that provide evidence for a common, intersubjective perception of spatial sonic phenomena created by the IKO. The experiments are designed on the basis of a hierarchical model of spatiosonic phenomena that exhibit increasing complexity, ranging from a single static sonic object to combinations of multiple, partly moving objects. The results are promising and explore new compositional perspectives in spatial computer music.