Békésy's interest in improving telephone communication led him eventually to make observations on the mechanical properties of the basilar membrane. For apical parts of the membrane he obtained resonance curves with steep high‐frequency slopes and gradual low‐frequency slopes. Tuning curves for auditory‐nerve fibers in anesthetized cats also show significant low‐frequency tails. Even fibers with high characteristic frequencies (CF) respond to tones throughout a wide range of low and middle frequencies. For low‐frequency tones at moderate and high stimulus levels the responses of high‐CF fibers tend to be time‐locked either to the same phase of the stimulus or to a phase that differs by a half cycle. For complex stimuli such as speech, which contains many low‐frequency components, these fibers behave as broadly tuned elements, discharging with time patterns that are principally determined by the temporal characteristics of the acoustic waveform. Results of experiments using low‐ and high‐frequency masking stimuli reinforce the view that responses of high‐CF fibers to low‐frequency stimuli should not be ignored in theories that seek to describe the role of the auditory nerve in speech communication.