Proximity of surfaces - acoustic and perceptual effects

The audibility of the acoustic effect of a reflective surface close to a subject is studied with measurements and psychoacoustic listening tests. The effect is measured with a reflective surface in anechoic and reverberant conditions using a binaural dummy head, and the results are compared with results from a simple image-source model of the situation. The effects caused by first reflection and interaction between the subject and the surface are shown. A listening experiment is conducted where the ability of subjects to perceive the distance of a surface is measured. Some of the listeners are shown to conduct the task reliably, and others provide either a random response or consistently reversed responses. This shows that the acoustic cues of the distance of the object are audible but do not always lead to correct perception of proximity to a surface.