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.

The use of high-density loudspeaker arrays (HDLAs) has recently experienced rapid growth in a wide variety of technical and aesthetic approaches. Still less explored, however, are applications to interactive music with live acoustic instruments. How can immersive spatialization accompany an instrument already with its own rich spatial diffusion pattern, like the grand piano, in the context of a score-based concert work? Potential models include treating the spatialized electronic sound in analogy to the diffusion pattern of the instrument, with spatial dimensions parametrized as functions of timbral features. Another approach is to map the concert hall as a three-dimensional projection of the instrument's internal physical layout, a kind of virtual sonic microscope. Or, the diffusion of electronic spatial sound can be treated as an independent polyphonic element, complementary to but not dependent upon the instrument's own spatial characteristics. Cartographies (2014), for piano with two performers and electronics, explores each of these models individually and in combination, as well as their technical implementation with the Meyer Sound Matrix3 system of the Südwestrundfunk Experimentalstudio in Freiburg, Germany, and the 43.4-channel Klangdom of the Institut für Musik und Akustik at the Zentrum für Kunst und Media in Karlsruhe, Germany. The process of composing, producing, and performing the work raises intriguing questions, and invaluable hints, for the composition and performance of live interactive works with HDLAs in the future.

Composers of electroacoustic music have developed and creatively implemented various spatialization techniques for multichannel loudspeaker setups. What is not known is which of these spatialization techniques is most effective for exploiting the extended creative possibilities available in multidimensional sound. This article discusses an experiment investigating the perception of the spatial attributes of “envelopment” and “engulfment” within a high-density loudspeaker array. The spatialization techniques used in the experiment were timbre spatialization, spectral splitting, amplitude point-source panning, and dynamic spectral subband decorrelation. Three loudspeaker setups, or spatial dimensions, were investigated: horizontal-only; elevated-only; and three-dimensional, which consisted of both horizontal and elevated loudspeaker setups. Results suggest that dynamic spectral subband decorrelation was perceived as both the most enveloping and the most engulfing technique when compared to other techniques in these experimental loudspeaker configurations. We propose that the experimental results can be successfully implemented when composing electroacoustic music to exploit the creative possibilities in a high-density loudspeaker array or in other multichannel loudspeaker configurations.

This article documents a personal journey of compositional practice that led to the necessity for working with high-density loudspeaker arrays (HDLAs). I work with textural composition, an approach to composing real-time computer music arising from acousmatic and stochastic principles in the form of a sound metaobject. Textural composition depends upon highly mobile sounds without the need for trajectory-based spatialization procedures. In this regard, textural composition is an intermediary aesthetic—between “tape music” and real-time computer music, between sound objects and soundscape, and between point-source and trajectory-based, mimetic spatialization. I begin with the aesthetics of textural composition, including the musical and sonic spaces it needs to inhabit. I then detail the techniques I use to create textures for this purpose. I follow with the spatialization technique I devised that supports the aesthetic requirements. Finally, I finish with an example of an exception to my techniques, one where computational requirements and the HDLA required me to create a textural composition without my real-time strategies.

This article discusses the advantages of spatial audio, in general, followed by strategies for applying spatial components to composition. The discussion then looks ahead to questions that may be solved by future implementations of spatial software and hardware. Despite the fact that technical systems for spatial audio have been in use since the 1950s, spatial concepts have not been widely integrated into the compositional process. This is because they involve a complex interaction of several phenomena, all of which play a role in the construction and perception of music. This article presents an analysis of the advantages of spatial audio for perception and provides examples of the decomposition of sonic material with the help of spatial properties, as well as a discussion of limitations in spatial construction and perception. Archival strategies for spatial audio are also briefly discussed.