Hearing Research Center, Boston University, Boston, Massachusetts 02215, USA.
J Acoust Soc Am. 2011 Jul;130(1):324-33. doi: 10.1121/1.3596476.
Two experiments explored how frequency content impacts sound localization for sounds containing reverberant energy. Virtual sound sources from thirteen lateral angles and four distances were simulated in the frontal horizontal plane using binaural room impulse responses measured in an everyday office. Experiment 1 compared localization judgments for one-octave-wide noise centered at either 750 Hz (low) or 6000 Hz (high). For both band-limited noises, perceived lateral angle varied monotonically with source angle. For frontal sources, perceived locations were similar for low- and high-frequency noise; however, for lateral sources, localization was less accurate for low-frequency noise than for high-frequency noise. With increasing source distance, judgments of both noises became more biased toward the median plane, an effect that was greater for low-frequency noise than for high-frequency noise. In Experiment 2, simultaneous presentation of low- and high-frequency noises yielded performance that was less accurate than that for high-frequency noise, but equal to or better than for low-frequency noise. Results suggest that listeners perceptually weight low-frequency information heavily, even in reverberant conditions where high-frequency stimuli are localized more accurately. These findings show that listeners do not always optimally adjust how localization cues are integrated over frequency in reverberant settings.
两个实验探索了含有混响能量的声音的频率内容如何影响声音定位。使用在日常办公室中测量的双耳房间脉冲响应，在正面水平平面上模拟了来自十三个侧面角度和四个距离的虚拟声源。实验 1 比较了中心频率分别为 750 Hz（低）或 6000 Hz（高）的一个倍频程宽噪声的定位判断。对于两种带限噪声，感知的侧面角度都随声源角度单调变化。对于正面声源，低频和高频噪声的感知位置相似；然而，对于侧面声源，低频噪声的定位准确性低于高频噪声。随着声源距离的增加，两种噪声的判断都更加偏向于中间平面，低频噪声的效果大于高频噪声。在实验 2 中，同时呈现低频和高频噪声的表现不如高频噪声准确，但与低频噪声一样或更好。结果表明，即使在高频刺激定位更准确的混响条件下，听众也会在感知上严重加权低频信息。这些发现表明，在混响环境中，听众并不总是最优地调整如何在频率上整合定位线索。
