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Figure 5. Screenshot from wave-based simulation of sound propagation in the Experimental Media and Performing Arts Center Concert Hall, Troy, NY.
proximation for asymptotically high frequencies, when the wavelength of sound is much smaller than the dimensions of room surfaces but not for low frequencies or wave behav- iors such as diffusion and diffraction. Wave-based modeling requires approximating the solution to the wave equation, typically using finite volume, finite element, or boundary el- ement methods. These methods have existed for many years, but computational complexity has limited widespread use in concert hall acoustical design. Figure 5 shows a screenshot from a wave-based simulation, modeled as part of a research effort to highlight its potential utility in concert hall acous- tics (Hochgraf, 2015). By harnessing the computing power of parallelized finite-volume simulations over multiple cloud- based graphics-processing units (GPUs), wave-based mod- eling may become widely available and computationally ef- ficient very soon, allowing acousticians to test their designs with more accuracy and reliability (Hamilton and Bilbao, 2018).
An auralization will never replace the real experience of lis- tening to music in a concert hall because it does not enable direct, engaging communication between musicians and lis- teners. As a musician and frequent audience member myself, I look forward to more opportunities in the future to draw from these real listening experiences and to use auralization as a research and design tool to support innovative, “excel- lent” design.
Acknowledgments
I thank Alban Bassuet, Timothy Foulkes, Eckhard Kahle, Scott Pfeiffer, Rein Pirn, Paul Scarbrough, and Robert Wolff for sharing their candid thoughts in interviews on concert hall acoustical design. I am also especially grateful to Jonah Sacks and Ben Markham for their feedback and mentorship.
References
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