Scheffers M T
J Acoust Soc Am. 1984 Aug;76(2):428-34. doi: 10.1121/1.391134.
An experiment was carried out, investigating the relationship between the just noticeable difference of fundamental frequency (jndfo) of three stationary synthesized vowel sounds in noise and the signal-to-noise ratio. To this end the S/N ratios were measured at which listeners could just discriminate a series of changes in fo in the range from 10% to 0.5%. Similar measurements were obtained for pulse trains and for pure tones as a reference for the results. A measure of S/N ratio based on an approximation of the critical bandwidth appeared to provide a fairly good predictor of the masked threshold of each signal, measured in a second experiment. Using this measure, it was found that a given change in the fundamental of a pulse train could be discriminated at a lower S/N ratio than in a pure tone with a frequency equal to that fundamental. The results for the vowel sounds were found to be in between those for a low-frequency pure tone and those for a pulse train. Owing to the signal-generation method (viz., changing fo by changing the sampling frequency), three cues could in principle be used to discriminate a change in the fundamental of a vowel: A change in the residue pitch, a change in the pitch of a single prominent harmonic, or a change in the spectral envelope of the signal. It can be inferred from the results that the subjects used that particular cue which yielded best performance. Which cue was optimal depended not only on the vowel but also on fo and on the presented change in fo.(ABSTRACT TRUNCATED AT 250 WORDS)
进行了一项实验，研究三种稳态合成元音在噪声中的基频刚可察觉差异（jndfo）与信噪比之间的关系。为此，测量了听众能够刚好辨别出基频在10%至0.5%范围内一系列变化时的信噪比。对于脉冲序列和纯音也进行了类似测量，作为结果的参考。基于临界带宽近似的信噪比测量方法似乎能很好地预测在第二个实验中测得的每个信号的掩蔽阈值。使用该测量方法发现，与频率等于该基频的纯音相比，脉冲序列基频的给定变化能在更低的信噪比下被辨别出来。元音的结果介于低频纯音和脉冲序列的结果之间。由于信号生成方法（即通过改变采样频率来改变基频），原则上可以使用三种线索来辨别元音基频的变化：残余音高的变化、单个突出谐波音高的变化或信号频谱包络的变化。从结果可以推断，受试者使用了产生最佳表现的特定线索。哪个线索是最优的不仅取决于元音，还取决于基频以及基频的呈现变化。（摘要截断于250字）
