Calibration of Consonant Perception to Room Reverberation.

Abstract

Purpose We examined how consonant perception is affected by a preceding speech carrier simulated in the same or a different room, for different classes of consonants. Carrier room, carrier length, and carrier length/target room uncertainty were manipulated. A phonetic feature analysis tested which phonetic categories are influenced by the manipulations in the acoustic context of the carrier. Method Two experiments were performed, each with nine participants. Targets consisted of 10 or 16 vowel-consonant (VC) syllables presented in one of two strongly reverberant rooms, preceded by a multiple-VC carrier presented in either the same room, a different reverberant room, or an anechoic room. In Experiment 1, the carrier length and the target room randomly varied from trial to trial, whereas in Experiment 2, they were fixed within a block of trials. Results Overall, a consistent carrier provided an advantage for consonant perception compared to inconsistent carriers, whether in anechoic or differently reverberant rooms. Phonetic analysis showed that carrier inconsistency significantly degraded identification of the manner of articulation, especially for stop consonants and, in one of the rooms, also of voicing. Carrier length and carrier/target uncertainty did not affect adaptation to reverberation for individual phonetic features. The detrimental effects of anechoic and different reverberant carriers on target perception were similar. Conclusions The strength of calibration varies across different phonetic features, as well as across rooms with different levels of reverberation. Even though place of articulation is the feature that is affected by reverberation the most, it is the manner of articulation and, partially, voicing for which room adaptation is observed.