Virtual acoustics in multimedia production—Beyond enhancing the acoustics of concert halls

Abstract

The paper describes a range of applications of virtual acoustics, the rendering of artificial acoustic spaces, which allow musicians to interact with ambient spaces created in real time. With a number of loudspeakers suitably distributed within a physical enclosure, such a projection system can be used to introduce a range of sound fields, which may effectively transform the acoustic environment to become a creative partner in multimedia production. A necessary component in this system is a low-latency, high-resolution multichannel convolution engine that converts a live audio signal into a structured ambient response, creating a scene in real time. Scenes can be changed to suit various goals of production and sonic narration. A number of techniques have been used to capture and modify impulse responses including temporal segmentation, shaping of magnitude envelope, noise reduction, spectral enrichment, time shifting and alignment, and parallel and sequential convolution. With these methods, artists may interact with novel acoustic responses as if they were musical instruments. Artists claim that many of the familiar as well as novel acoustic responses stimulate their creativity. Flexible variable virtual acoustics opens additional creative possibilities when employed as a component of a recording studio, either directly or when rendered over headphones.