Spatial hearing emerges from the integration of auditory, multisensory, and motor information, and is enhanced in natural conditions through active listening, where head and body movements provide dynamic cues that improve localisation accuracy and perceptual stability. This principle is central to immersive audio research in Virtual and Augmented Reality (VR/AR), where binaural rendering based on Head-Related Transfer Functions (HRTFs) and room acoustic cues enables the reproduction of interaural, monaural, and distance information. Beyond acoustics, bodily engagement (i.e., reaching toward sound sources) further supports spatial adaptation. These technologies enable controlled experimental protocols for assessment and training in both normal-hearing and hearing-impaired populations. One such paradigm is SPHERE, originally developed to study three-dimensional sound localisation in ecologically valid conditions and later applied to training and rehabilitation, including for cochlear implant users. In its original implementation, participants localise sounds presented via a physically moved loudspeaker and respond either through active exploration or under static listening constraints, while head, eye, and hand movements are tracked to analyse localisation accuracy, motor behaviour, and search strategies. However, reliance on a human operator limits reproducibility and scalability. This work introduces a fully virtualised SPHERE implementation using an immersive binaural rendering framework, preserving the original spatial configuration while enabling real-time multimodal tracking. The system also evaluates the impact of HRTF individualisation by comparing generic and personalised filters. Performance is validated against the original loudspeaker-based paradigm to assess ecological validity. Preliminary results regarding the system’s effectiveness as a research and clinical tool will be presented at the conference.
