Virtual acoustic environments enable the creation and simulation of realistic and ecologically valid daily-life situations with applications in hearing research and audiology. Hereby, reverberant indoor environments play an important role. For real-time applications, simplifications in the room acoustics simulation are required, however, it remains unclear what acoustic level of detail (ALOD) is necessary to capture all perceptually relevant effects. This study investigates the effect of varying ALOD in the simulation of three different real environments, a living room with a coupled kitchen, a pub, and an underground station. ALOD was varied by generating different numbers of image sources for early reflections, or by excluding geometrical room details specific for each environment. The simulations were perceptually evaluated using headphones in comparison to binaural room impulse responses measured with a dummy head in the corresponding real environments. The study assessed the perceived overall difference for a pink pulse, and a speech token. Furthermore, plausibility and externalization were evaluated. The results show that a strong reduction in ALOD is possible while obtaining similar plausibility and externalization as with dummy head recordings. The number and accuracy of early reflections appear less relevant, provided diffuse late reverberation is appropriately accounted for.

翻译：虚拟声环境能够创建并模拟真实且生态有效的日常生活场景，广泛应用于听力研究与听力学领域。其中，混响室内环境尤为重要。在实时应用中，需对室内声学模拟进行简化，但尚不明确需要何种声学细节层次（Acoustic Level of Detail, ALOD）才能捕获所有感知相关效应。本研究探究了在三种不同真实环境（带耦合厨房的客厅、酒吧及地铁站）的模拟中，变化ALOD对感知的影响。ALOD的变化方式包括生成不同数量的早反射镜像声源，或排除各环境特有的几何细节。通过耳机对比相应真实环境中用假人头部测量的双耳房间脉冲响应，对模拟结果进行感知评估。研究分别以粉红脉冲和语音片段评估感知整体差异，并进一步评价了逼真度与外部化效果。结果表明：在获得与假人头部记录相当的逼真度与外部化效果时，ALOD可大幅降低。只要弥散晚期混响得到恰当处理，早反射的数量与精度似乎并非关键因素。