Page 48 - Winter 2020

FEATURED ARTICLE
Simulation-Based Auralization of Room Acoustics1
Lauri Savioja and Ning Xiang
Introduction
Sound quality of concert halls and auditoriums is a matter of taste because there are as yet no overall objective measurable criteria that describe the quality of acoustics in the room. Instead, sound quality is a subjective measure that is often determined by listening in the space. For this reason, it is essential that the acoustic designers of concert halls and auditoriums get a chance to listen to the expected outcome as early as possible, preferably even before construction has started (Hochgraf, 2019).
Providing such an opportunity is the goal of simulation- based auralization, which aims to produce as authentic an auditory experience as possible by utilizing only the
1 This article derives from a special issue of The Journal of the Acoustical Society of America (JASA) on room-acoustic simulation and auralization edited by Lauri Savioja and Ning Xiang (acousticstoday.org/room-acoustics).
geometry and acoustic treatment information of the space. Overall, the main ingredients of room-acoustic auralization are room-impulse responses, anechoic recordings, and spatial sound reproduction systems, as illustrated in Figure 1. The room-impulse responses can be obtained in terms of either simulation or measurement. The measurement-based auralization is applicable when an existing space or a scale model is available to be auralized. In this paper, we focus on different room-acoustic modeling techniques and their use in simulation-based modeling and binaural auralization. Other approaches, including measurement-based (Schroeder, 1970; Xiang and Blauert, 1993) and multichannel (Blauert and Rabenstein, 2017) auralization are out of our current scope.
Computational modeling and auralization in room acoustics were conceived in the early 1960s when Schroeder et al. (1962) presented the basic ideas. In its early stage, room- acoustic computer simulation was developed mostly without audible components (Krokstad et al., 1968; Schroeder, 1970).
Figure 1. Room acoustic auralization can be based either on simulations or measurements, and the results can be made audible via headphones or loudspeakers. The main component of auralization is the convolution of room-impulse responses with anechoic signals.
48 Acoustics Today • Winter 2020 | Volume 16, issue 4
©2020 Acoustical Society of America. All rights reserved.
https://doi.org/10.1121/AT.2020.16.4.48