Low-Rank Multi-Channel Fast Convolution for Real-Time Auralization of Church Acoustics

Interactive auralization of room acoustics is a key research tool for investigating the impact of performance space acoustics on music practice. In the context of early music, particularly plainchant and polyphony, the historically relevant performance spaces are usually churches. The interactive auralization of church acoustics is highly challenging due to the long reverberation times involved, which conflict with the real-time, low-latency requirements of interactive systems. This paper investigates the use of low-rank compression with partially invariant transformation to achieve low-latency convolution in real-time multi-channel auralization systems. In previous work, we have demonstrated that low-rank joint compression of Room Impulse Responses (RIRs) measured in the same room facilitates low-latency convolution while preserving the acoustic properties of the RIRs. This study expands on the method to achieve low-latency convolution for auralization filters derived from a space-time analysis of RIR measurements. A case study of the interactive auralization of the 16th-century Nassau Chapel in Brussels is presented to demonstrate how significant computational savings can be achieved while preserving auralization quality.