Department of Communicative Disorders, Auditory Behavioral Research Laboratory, University of Wisconsin, Madison, Wisconsin 53706, USA.
J Acoust Soc Am. 2010 Jan;127(1):350-60. doi: 10.1121/1.3263606.
A computational formula is derived for estimating the constraints limited auditory sensitivity imposes on auditory identification of the material and geometric properties of struck bars. The formula combines a model of the transverse motion of the bar with empirical psychometric functions to map out "null" regions in the bar's physical parameter space where changes in the frequency, amplitude, and decay of partials are likely below threshold for detection. Parameters of the physical space include bar density, Young's modulus, fluid and viscoelastic damping factors, bar length, and bar cross-sectional area (as related to bar shape and hollowness). The formula is used to estimate the possible effect of limited sensitivity in past studies on the auditory identification of bar attributes. The results suggest that sensitivity may, indeed, have played a role in some studies, and that apparent discrepancies in results may be understood based on whether the predominant source of damping was internal or external to the bar. The formula identifies conditions representing an expected bound on identification performance and thereby may be used to aid in the design of future studies for which the struck bar is the sound source of choice.
推导出了一个计算公式，用于估计听觉灵敏度对敲击杆的材料和几何性质的听觉识别的限制。该公式将杆的横向运动模型与经验心理物理函数相结合，以绘制出杆的物理参数空间中的“零”区域，在这些区域中，部分频率、幅度和衰减的变化可能低于检测阈值。物理空间的参数包括杆的密度、杨氏模量、流体和粘弹性阻尼因子、杆的长度以及杆的横截面积（与杆的形状和空心有关）。该公式用于估计过去研究中灵敏度限制对杆属性听觉识别的可能影响。结果表明，灵敏度确实可能在某些研究中起作用，并且基于阻尼的主要来源是杆内还是杆外，可以理解结果的明显差异。该公式确定了代表识别性能预期界限的条件，因此可用于辅助未来研究的设计，在这些研究中，敲击杆是首选的声源。
