Perceptual Evaluation of Spatial Audio for “Audio Nomad” Augmented Reality Artworks

Abstract

Audio Nomad is a three-year art/science research collaboration on the creative and technological potentials of location-sensitive, mobile spatial audio. The first Audio Nomad productions were two versions of Syren – a ship-based multi-speaker installation using the ship’s position from a GPS receiver to render a two-dimensional soundscape. New work including Virtual Wall (Berlin) will create a personal location-sensitive spatial soundscape on headphones using a portable computer, GPS receiver and digital compass. The technological intent is to enable the artist to augment real world objects and spaces with sounds perceived to emanate from them. It is important to know the maximum perceivable accuracy of the intended augmented reality effect, given human and technology limitations, even if soundscape design doesn’t always require maximum precision. Ultimately, authoring software features will inform the artist of afforded perceptual quality, enabling better utilisation of the medium’s potential. Few similar projects have been produced to date and fewer have published quantitative perceptual evaluation research. This paper reviews the field and describes present experimental results and future work on the perceptual evaluation of binaural spatial audio for mobile augmented reality, especially Audio Nomad artworks.