A model of pitch perception is presented. The model involves an array of delay lines and inhibitory gating neurons. In response to a periodic sound, a {\em minimum}\ appears in the pattern of outputs of the inhibitory neurons, at a lag equal to the period of the sound. The position of this minimum is the cue to pitch. The model is similar to the autocorrelation model of pitch, multiplication being replaced by an operation similar to subtraction, and maxima by minima. The two models account for a wide class of pitch phenomena in very much the same way. A first aim of this paper is to demonstrate this fact. A second aim is to argue that the cancellation model has several advantages over autocorrelation: it is closely related to the operation of harmonic cancellation that can account for segregation of concurrent harmonic stimuli, it shows a certain degree of sensitivity to phase, and it can be generalized to the perception of multiple pitches.