Schematic spectra for four example stimuli for F0 = 100 Hz. For these examples, the value of N was 3 (top) or 7 (bottom), and the value of nB was 4 (left) or 8 (right). In the figure, the harmonics in group B occur at integer multiples of 100 Hz. In the actual experiment, the F0 of the harmonics in group B was shifted upward by 0.5ΔF in one interval of a trial and downward by 0.5ΔF in the other interval. The value of ΔF was varied to estimate the F0DL.
Geometric mean F0DLs for experiment 1 for F0 = 50 Hz (top) and 200 Hz (bottom). The F0DL is plotted as a percentage of F0 as a function of the harmonic rank, N, of the lowest harmonic in group B. The frequency of the lowest component in group B is shown at the top. Parameters are the starting phase of the components (filled symbols = random, open symbols = cosine) and the number of components, nB, in group B (squares = 4, triangles = 8). Error bars indicate ± one standard error of the mean. The vertical dashed line indicates the boundary between resolved and unresolved harmonics based on the assumption that a harmonic needs to be separated from neighboring harmonics by 1.25ERBN or more for it to be resolved.
As Fig. 2 , but for experiment 2 and for F0 = 100 and 200 Hz.
Comparison of the data for experiments 1 and 2 for the cosine-phase stimuli with F0 = 200 Hz. Parameters are nB (circles = 4, diamonds = 8) and whether PPA cues were effective (experiment 1, filled symbols) or ineffective (experiment 2, open symbols). Otherwise as Fig. 2 .
F0DLs from the supplementary experiment for the following conditions: (1) With the levels of the lowest 15 components selected so that each would have a loudness level of 40 phons if presented in isolation, without any masker (filled triangles); (2) with the levels of the components in groups A and B selected as in (1), with narrowband noise in the spectral gaps (open triangles); (3) with the levels of the components in groups A and B equal, with narrowband noise in the spectral gaps (open squares). Data from experiment 1 for F0 = 50 Hz, nB = 4, random phase, equal-level components are shown by filled squares.
F0DLs from the supplementary experiment for random- and cosine-phase conditions. In both cases, the levels of the lowest 15 components were selected so that each would have a loudness level of 40 phons with narrowband noise in the spectral gaps.
F0DLs plotted against the width of group B expressed in ERBN-number, with unit Cams.
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