The rapid decline in interaural-time-difference sensitivity for pure tones is explained by a single frequency-channel model.

Human sensitivity to fine-structure interaural time differences declines with increasing frequency at an incredible rate of 90 dB/octave above 1200 Hz. This is best explained by initial peripheral processing (auditory filtering and off-frequency processing), not a central neural limitation such as a decline phase locking. A binaural model with a single dominant channel near 700 Hz can explain these data, which contradicts the classic formulation of binaural display that utilizes a matrix of neurons tuned to a range of best frequencies and interaural time differences.