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The question is sometimes raised as to whether the temporal aspects of acoustic signals are analyzed solely at the basal end of the organ of Corti. Three series of experiments were performed on the differential masking of stimuli known to be analyzed by the auditory system on the basis of temporal characteristics. First, a masking‐level difference (MLD) experiment was performed. Binaural masked thresholds (under S0 and Sπ conditions) of a 500‐Hz tone were measured and compared to similar thresholds taken while a loud high‐pass noise, cut off at 800, 1000, 1200, 1600, 2400, or 4800 Hz, was simultaneously presented. Any basal cochlear contribution to the MLD was predicted to be at least partially disrupted by the extra masker (since it would be serving to keep the high‐frequency segments of the basilar membrane busy). Similarly, perception of the Wood effect (a monaural phase effect) and of binaural beats was tested with and without such high‐pass bands of noise. Except for those cutoff frequencies that allowed noise energy to interfere directly with the signal, the influence of the extra masking was negligible. Because a fatigued ear might behave differently, the experiments were repeated following intense high‐frequency exposures (and, in one case, with a subject having a precipitous high‐frequency hearing loss). The results were similar. Implications of these findings are discussed. [Investigation supported in part by the National Institute of Neurological Diseases and Blindness, National Institutes of Health, U. S. Department of Health, Education, and Welfare.]