Early reflection is an important component in an enclosedsound field. Due to the precedence effect, the early reflection maynot be the dominant factor in sound source localization;however,it still has obvious influenc...Early reflection is an important component in an enclosedsound field. Due to the precedence effect, the early reflection maynot be the dominant factor in sound source localization;however,it still has obvious influences on spatial position, loudness, timbre,and etc. Till now, there have sparse studies on evaluation of theaudible threshold of early reflections with lacking of general andquantitative results. This work investigated the audible thresholdof early reflection with a simplified sound field model undervarious experimental conditions including the combination ofeight incidence angles and five time delays. Three-down-one-upadaptive strategy with three-interval three-alternativeforced-choice (3I-3AFC) paradigm was used due to its efficiencyand robustness. Results indicate that (1) the audible threshold ofearly reflections decreases monotonically with increasing timedelay relative to the direct sound. Furthermore, a linear equationbetween early reflection threshold and time delay is establishedwith correlation coefficient higher than 0.9;(2) When the directsound and the reflection locate in the same half-plane, the audiblethreshold of early reflections decreases with increasing angledeviation between the direct sound and the reflection. Moreover,a front-back symmetry of early reflection threshold is observedfor stimuli below 5 kHz;(3) Considerable variations in earlyreflection threshold are found among individuals, especially atlarge angle deviation and time delay of early reflections relativeto the direct sound.展开更多
基金supported by the National NatureScience Foundation of China (No. 11474103)Guangdong ModernVision-audio Information Engineering Technology Research Center(Guangzhou University, 2017.12-2019.12).
文摘Early reflection is an important component in an enclosedsound field. Due to the precedence effect, the early reflection maynot be the dominant factor in sound source localization;however,it still has obvious influences on spatial position, loudness, timbre,and etc. Till now, there have sparse studies on evaluation of theaudible threshold of early reflections with lacking of general andquantitative results. This work investigated the audible thresholdof early reflection with a simplified sound field model undervarious experimental conditions including the combination ofeight incidence angles and five time delays. Three-down-one-upadaptive strategy with three-interval three-alternativeforced-choice (3I-3AFC) paradigm was used due to its efficiencyand robustness. Results indicate that (1) the audible threshold ofearly reflections decreases monotonically with increasing timedelay relative to the direct sound. Furthermore, a linear equationbetween early reflection threshold and time delay is establishedwith correlation coefficient higher than 0.9;(2) When the directsound and the reflection locate in the same half-plane, the audiblethreshold of early reflections decreases with increasing angledeviation between the direct sound and the reflection. Moreover,a front-back symmetry of early reflection threshold is observedfor stimuli below 5 kHz;(3) Considerable variations in earlyreflection threshold are found among individuals, especially atlarge angle deviation and time delay of early reflections relativeto the direct sound.
