Connecting the sense of envelopment to specific components of the sound field using perceptually motivated auralizations

Abstract

Envelopment is known to be a key attribute related to overall room impression. Despite this importance, limited research has been done to identify the specific components of the sound field that contribute to envelopment. The goal of this study was to determine the timing and spatial distribution of reflections contributing to envelopment. A subjective study was conducted using a range of simulated auralizations, which were played back over a three-dimensional loudspeaker array in an anechoic chamber. For each auralization, subjects rated their perceived envelopment. A real-time acoustic simulation program was developed in Max to generate the signals, which simulated early sound with the image-source method and late sound with statistical reverberation. When creating the stimuli, the program produced immediate auditory feedback in response to adjusting the input parameters. The signals were quantified through impulse response measurements to ensure a wide range of conditions. The subjects’ envelopment ratings were correlated to different components of the sound field, to evaluate how specific arrival time of reflections and spatial characteristics contribute to envelopment. These results could possibly be used to determine the effectiveness of existing envelopment metrics and potentially contribute to developing a new measure to predict envelopment. [Work supported by NSF Award-1302741.]