Dynamic spatial rendering of early and late reverberation of virtual acoustic scenes

Hearing out a target sound source in the presence of other sources is affected by the sources' level, spectrum at the ears and binaural configuration of interaural coherence and phase. We focus on creating reproducible life-like, interactive laboratory test situations of spatial unmasking with moving sound sources and reverberation. The real-time Simulated Open Field Environment (rtSOFE) is an open-source software package for simulating and auralizing static, moving and interactive sound sources in virtual rooms via headphones or via loudspeaker arrays. In order to achieve high simulation update rates, early and late reverberation parts are rendered in different rtSOFE instances or taken pre-computed or measured from a file. Configuration options and different use cases of rtSOFE are discussed. These include offline room acoustic simulation, interactive virtual reality scenarios and auditory modeling in Matlab with on-the-fly computation of room impulse responses. New features in the upcoming rtSOFE version 1.2 are presented as well as an approach for spatial rendering of scattered energy. It uses spatial channels which are fed with the scattered energy and which feed back energy to other spatial channels similar to a feedback-delay network. The virtual acoustic scenario is described as a defined acoustic environment in which a particular configuration of sources and receivers characterizes an acoustic scene. We present two verified open-source scenes for audiological research which take place on the platform of a virtual twin model of an underground station in Munich.