Real and Virtual Lecture Rooms: Validation of a Virtual Reality System for the Perceptual Assessment of Room Acoustical Quality

Enhancing the acoustical quality in learning environments is mandatory, especially for Hearing Aids (HAs) users. When in-field evaluations cannot be performed, Virtual Reality (VR) can be adopted for the acoustical quality assessment of existing and new buildings, contributing to the acquisition of subjective impressions in lab settings. To ensure an accurate spatial reproduction of the sound field in VR also for HAs users, multispeaker-based systems can be employed to auralize a given environment. However, most systems are effortful due to costs, size and construction. This work deals with the validation of a VR-system based on a 16-speaker-array synced with a VR-headset, arranged to be easily replicated in small non-anechoic spaces and suitable for HAs users. Both objective and subjective validations are performed against a real university lecture room of 800 m3 and with 2.3 s of Reverberation Time at mid-frequencies. Comparisons of binaural and monoaural room acoustic parameters are performed between measurements in the real lecture room and its lab reproduction. To validate the AudioVisual experience, 32 normal-hearing subjects were administered the Igroup Presence Questionnaire (IPQ) on the overall sense of perceived presence. The outcomes confirm that the system is a promising and feasible tool to predict the perceived room acoustical quality.