耳机重发下延迟时间对空间分离前向掩蔽效应影响的研究

采用耳机虚拟声重发的方法,探讨了掩蔽信号和被掩蔽信号在水平面方向分离的情况下延迟时间对前向掩蔽效应的影响。结果表明,掩蔽阈值有随延迟时间增加而下降较多的总体趋势。而且,在水平面空间分离的情况下,掩蔽阈值存在差值,最大为15 dB左右。但在掩蔽声的声压级较大时(如70 dB),在延迟时间20~40 ms处出现掩蔽阈值差值的小幅度上升。通过对时间积分效应和基膜响应的分析,这一实验结果能得到合理的解释。

The influence of time delay on forward masking when spatially separated sound image reproduced with headphone

With headphone virtual reproduction,the influence of delay time between masker and masked signal on forward masking when sound images are virtually spatial separated in azimuth is studied.The result shows that the thresholds tend to drop by a relative large amount with the increase in delay time.Furthermore,in case of spatial separation,there are differences of thresholds,the largest one is about 15 dB.However,when masker is 70 dB,the difference of the thresholds increases a little as the delay time increases from 20 ms to 40 ms.Based on the analysis of time integration effect and basilar membrane response,the results can be explained reasonably.