Spatial soundscape superposition, Part II: Signals and systems

We present an analytical framework for a cognitively informed organization of signals involved in computational representations of spatial soundscape superposition, defined here as "procedural superposition," building on the accompanying article Part I, where we discussed physical (acoustical) and perceptual (subjective and psychological) frameworks for soundscape representations in virtual auditory displays. Exploiting multimodal sensation and mental models of situations and environments, convention and idiom can tighten listeners' apprehension of an auditory scene, using metaphor and relaxed expectation of sonorealism to enrich communication. Besides physical and psychological combinations, procedural (logical and cognitive) superposition considers metaphorical mappings between audio sources and virtual location, including such aspects as separation of visual and auditory perspectives; separation of direction and distance; parameterized binaural and spatial effects, including directionality; range-compression and indifference; layering of soundscapes; "audio windowing" (analogous to graphical user interface windows), narrowcasting, and multipresence as a strategies for managing privacy; and rotation as revolution. These auditory display strategies leverage virtual relaxations of sonorealism to enable enhanced soundscape representation.