Abstract
Binaural synthesis systems can create virtual sound sources that are indistinguishable from reality. In Augmented Reality (AR) applications, virtual sound sources need to blend in with the real environment to create plausible illusions. However, in some scenarios, it may be desirable to enhance the natural acoustic properties of the virtual content to improve speech intelligibility, alleviate listener fatigue, or achieve a specific artistic effect. Previous research has shown that deviating from the original room acoustics can degrade the quality of the auditory illusion, often referred to as the room divergence effect. This study investigates whether it is possible to modify the auditory aesthetics of a room environment without compromising the plausibility of a sound event in AR. To accomplish this, the length of the reverberation tails of measured binaural room impulse responses are modified after the mixing time to change reverberance.A listening test was conducted to evaluate the externalization and audio-visual plausibility of an exemplary AR scene for different degrees of reverberation modification. The results indicate that externalization is unaffected even with extreme modifications (such as a stretch ratio of 1.8). However, audio-visual plausibility is only maintained for moderate modifications (such as stretch ratios of 0.8 and 1.2).