Evaluation of Three Auditory-Sculptural Qualities Created by an Icosahedral Loudspeaker

Abstract

The icosahedral loudspeaker (IKO) was previously established as an electroacoustic instrument enabling the musical creation and orchestration of sculptural sound phenomena in the room. This is technically achieved by manipulating the strengths of the available acoustic reflection paths by using the IKO’s acoustic beamforming capabilities. In its use, listeners perceive auditory sculptures whose characterization needs investigation. We present a proposed set of sculptural quality attributes directionality, contour, and plasticity and a series of listening experiments investigating them. The experiments employ documented beam layouts using a selected set of sounds as conditions, and they evaluate the recognizability, perceivable grading, and discernibility of the proposed sculptural qualities.

Design, Control, and Evaluation of Mixed-Order, Compact Spherical Loudspeaker Arrays

“…Although the vertical beamforming capacity is weaker compared with the IKO, the fourth-order horizontal beamforming design effectively exceeds the conventional thirdorder beamforming of the IKO, as used in previous tests and concerts. Because the analysis above is limited to technical beamforming measurements and metrics, this section addresses in greater detail Sharma, Frank, and Zotter (2019). Mean values are marked by dots, the gray ellipsoidal region marks the 95% confidence ellipse (Hotelling's T-squared distribution, in gray) around each condition.…”

“…Moreover, Wendt et al (2017b) and Zotter et al (2017) show that time-varying beamforming is capable of moving auditory objects through the interior of the playback environment. Sharma, Frank, and Zotter (2019) establish and evaluate three auditory sculptural attributes produced by a small set of signals laid out in static and time-varying beam compositions.…”

“…beamforming and exemplary practical tools required for its use (ambix and mcfx VST plugins). Wendt et al (2017b) and Sharma, Frank, and Zotter (2019) investigated auditory sculptures and their attributes that emerge for exemplary static and time-varying beam compositions, and hereby provide a descriptive framework for the artistic practice. In these beam compositions, sound is projected onto walls and baffles to produce auditory objects via acoustic reflections, essentially via horizontal beams, that are most effective.…”

“…Figure 13. Auditory sculptural attributes of the IKO and the new 3|9|3 prototype for the musical signals composed bySharma, Frank, and Zotter (2019). Mean values are…”

Software Tools for Flexible Control of Radiation Synthesis

“…These sound beams can excite reflective walls, yielding interesting effects in the perceived spatial impression, such as auditory objects that seem more distant than the loudspeaker system. When orchestrated musically, such auditory phenomena are sometimes referred to as sonic sculptures [9], [19]- [23], [38], [39].…”