Higher-Order Spatial Impulse Response Rendering: Investigating the Perceived Effects of Spherical Order, Dedicated Diffuse Rendering, and Frequency Resolution

Abstract

This article details an investigation into the perceptual effects of different rendering strategies when synthesizing loudspeaker array room impulse responses (RIRs) using microphone array RIRs in a parametric fashion. The aim of this rendering task is to faithfully reproduce the spatial characteristics of a captured space, encoded within the input microphone array RIR (or the spherical harmonic RIR derived from it), over a loudspeaker array. For this study, a higherorder formulation of the Spatial Impulse Response Rendering (SIRR) method is introduced and subsequently employed to investigate the perceptual effects of the following rendering configurations: the spherical harmonic input order, frequency resolution, and utilizing dedicated diffuse stream rendering. Formal listening tests were conducted using a 64-channel loudspeaker array in an anechoic chamber, where simulated reference scenarios were compared against the outputs of different methods and rendering configurations. The test results indicate that dedicated diffuse stream rendering and higher analysis orders both yield noticeable perceptual improvements, particularly when employing problematic transient stimuli as input. Additionally, it was found that the frequency resolution employed during rendering has only a minor influence over the perceived accuracy of the reproduction in comparison to the other two tested attributes.

Locating Image Sources from Multiple Spatial Room Impulse Responses

“…Thus, a Spatial Room Impulse Response (SRIR) can be analyzed in both temporal and spatial domain, which helps us to understand the acoustics of a room better and allows us to reproduce the acoustic behavior of the measured space faithfully. Parametric methods for processing SRIR, such as the Spatial Decomposition Method (SDM) [1], Spatial Impulse Response Rendering (SIRR) [2] or Higher-order SIRR (HO-SIRR) [3], have been a cornerstone of concert hall research in recent years [4,5]. Such techniques have enabled us to directly compare different spaces in numerous listening tests.…”

Six-Degrees-of-Freedom Parametric Spatial Audio Based on One Monaural Room Impulse Response

“…Parametric rendering is a promising approach to create perceptually plausible spatial audio renderings of high quality for applications with low computing capacity, such as AR applications. Most parametric encoding methods rely on SRIR measurements, such as first-order Ambisonics (FOA) or open array measurements [1,3,2,5,6], or even higher-order rigid-sphere array measurement [4,25]. Those methods usually auralize the sound field only at the measurement point for the listener's head orientation, i.e., the sound field is only rendered for 3 DoF.…”

“…A precomputed DOA pattern can also be used for spatialization, making use of multichannel RIRs to derive DOA estimates. For example DOAs estimated in the context of SDM with open microphone arrays exploiting time differences of arrival (TDOAs) or with B-format array using pseudo intensity vectors (PIVs) [3,24,1,25] can be passed to the spatialization. The direct sound and selected reflections are then assigned the DOAs listed according to the TOAs in the passed DOA vector.…”

Auralization based on multi-perspective ambisonic room impulse responses

“…The diffuse RIR part is decorrelated and mixed to all loudspeakers. A recent work [39] introduced a SIRR approach for higher-order input and moreover investigated the perceived effect of different SIRR configurations in comparison to the first-order spatial decomposition method (SDM).…”