An experimental investigation of binaural sound reproduction using a hybrid system based on parametric loudspeaker array

Traditional virtual sound reproduction systems often employ crosstalk cancellation filters to mitigate crosstalk paths, and then use conventional electro-dynamic loudspeaker (EDL) to reproduce the signal. However, crosstalk cancellation filters are deteriorated in the high-frequency range. In contrast, parametric array loudspeaker (PAL) has a high directivity and excellent performance in the mid-to-high frequency range, with effective natural channel separations. However, the PAL suffers from poor low-frequency response. This study presents a multi-loudspeaker (Hybrid) system that combines the PAL and EDL to achieve wideband virtual binaural sound reproduction. The proposed system uses the EDL to process signals below 1 kHz with the crosstalk cancellation method and employs the PAL to directly convolve with head-related transfer function (HRTF) for virtual sound reproduction above 1 kHz. It can achieve effective crosstalk cancellation and accurate virtual sound localization across a wide frequency range. Additionally, phase and magnitude equalization techniques are applied to achieve a flat frequency response of the Hybrid system. Two psychoacoustic experiments are conducted to compare the system’s localization accuracy and timbre perception with a conventional two-channel EDL. Experimental results demonstrate the Hybrid system reduces lateral localization errors and provides better subjective timbre perception. These findings provide robust experimental support for using the PAL-based hybrid systems in stereo sound reproduction, providing an effective solution for virtual acoustic environments.