Room-scale virtual reality (VR) affordance in movement and interactivity causes new challenges in creating virtual acoustic environments for VR experiences. Such environments are typically constructed from virtual interactive objects that are accompanied by an Ambisonic bed and an off-screen (“invisible”) music soundtrack, with the Ambisonic bed, music, and virtual acoustics describing the aural features of an area. This methodology can become problematic in room-scale VR as the player cannot approach or interact with such background sounds, contradicting the player’s motion aurally and limiting interactivity. Written from a sound designer’s perspective, the paper addresses these issues by proposing a musically inclusive novel methodology that reimagines an acoustic environment predominately using objects that are governed by multimodal rule-based systems and spatialized in six degrees of freedom using 3D binaural audio exclusively while minimizing the use of Ambisonic beds and non-diegetic music. This methodology is implemented using off-the-shelf, creator-oriented tools and methods and is evaluated through the development of a standalone, narrative, prototype room-scale VR experience. The experience’s target platform is a mobile, untethered VR system based on head-mounted displays, inside-out tracking, head-mounted loudspeakers or headphones, and hand-held controllers. The authors apply their methodology to the generation of ambiences based on sound-based music, sound effects, and virtual acoustics. The proposed methodology benefits the interactivity and spatial behavior of virtual acoustic environments but may be constrained by platform and project limitations.

3D audio spatializers for Virtual Reality (VR) can use the acoustic properties of the surfaces of a visualised game space to calculate a matching reverb. However, this approach could lead to reverbs that impair the tasks performed in such a space, such as listening to speech-based audio. Sound designers would then have to alter the room’s acoustic properties independently of its visualisation to improve speech intelligibility, causing audio-visual incongruency. As user expectation of simulated room acoustics regarding speech intelligibility in VR has not been studied, this study asked participants to rate the congruency of reverbs and their visualisations in 6-DoF VR while listening to speech-based audio. The participants compared unaltered, matching reverbs with sound-designed, mismatching reverbs. The latter feature improved D50s and reduced RT60s at the cost of lower audio-visual congruency. Results suggest participants preferred improved reverbs only when the unaltered reverbs had comparatively low D50s or excessive ringing. Otherwise, too dry or too reverberant reverbs were disliked. The range of expected RT60s depended on the surface visualisation. Differences in timbre between the reverbs may not affect preferences as strongly as shorter RT60s. Therefore, sound designers can intervene and prioritise speech intelligibility over audio-visual congruency in acoustically challenging game spaces.