A Low-Dimensional Projection of Sound Absorption Coefficients for a Scattering Delay Network Reverberator

Scattering delay networks (SDNs), a class of artificial reverberators with physically interpretable parameters, provide an efficient synthesis of room acoustics accounting for wall absorption properties. This paper builds upon a previously proposed highly parametrized and real-time implementation of an SDN, exposing octave-band absorption coefficients for each room wall. The individual manipulation of these coefficients can be challenging due to their high dimensionality. A 2D parameter space (2PS) is proposed to facilitate the navigation of the absorption coefficients. The 2PS is obtained using principal component analysis as an initial dimensionality reduction of a dataset of absorption coefficients, followed by a relaxation procedure to create a seamless 2D representation of the coefficients. A twofold evaluation of the proposed 2PS was conducted: (a) the 2PS was compared to the original space and the raw principal component analysis in a reverb matching task for the tuning of SDN coefficients, and (b) a usability test with expert audio professionals supported the potential of the 2PS from a user standpoint.