Perceptual adaptation to room acoustics and effects on speech intelligibility.

Abstract

The perceptual characteristics of sound in enclosed spaces are typically considered to be constant as a function of time, provided the source of sound also remains constant. Emerging evidence suggests, however, that at least for certain classes of room enclosures, the perceived acoustical contributions of the room decrease as listening time within the room is increased. A process of perceptual adaptation in which the acoustical contributions of the room are suppressed is likely responsible for this change. Here, a series of experiments is described that demonstrates objective improvements in speech intelligibility in reverberant rooms due presumably to room adaptation processes. Headphone-based auralization techniques were used to simulate the acoustics of various listening rooms used in the experiments, ranging from anechoic to highly reverberant space (broadband T60 = 3 s). When listeners were provided with brief (<10 s) room listening exposure via a carrier phrase prior to the test phrase used for intelligibility assessment, intelligibility improved by as much as 20%. Although variability in the effect was observed between listeners, it appears to require binaural input and is specific to moderately reverberant rooms (0.3 ⩽ T60 ⩽ 1 s). [Work supported by NIH R01DC008168.]