Spatial Sound, Part 1: Exploring the Impact of Listening Room on Perceptual Immersion

Room acoustics and sound reproduction systems shape the spatial sound character in a listening room, influencing sound quality. This study introduces a novel technique to assess the spatial character of room acoustics and sound reproduction systems, addressing a research gap in understanding spatial differences between listening environments. The technique was employed in a listening test where 15 assessors evaluated the impact of three listening rooms on perceptual immersion for music in 2.0 and 7.1 configurations using loudspeakers and binaural audio for headphones. The results indicate room reverberation enhances perceptual immersion, particularly with two-channel stereophonic setups. Surround speakers reduce room-induced effects when the music is mixed sufficiently enveloping, especially with distinct, nonreverberant surround elements. The results with headphones were similar but less pronounced. Assessors found the normal stereo tonally preferable to binaural conditions, but perceptions of immersiveness varied. Some described it as highly immersive, whereas others reported a lack of spatial depth, although it was perceived as supernaturally wide and effective compared with binaural sound. This highlights the challenge of transitioning from normal stereo to a spatialized mix in streaming services. Overall, the findings can enhance the immersive experience and even out perceptual differences between listening environments, including loudspeakers and headphones.