PURPOSE: To generate the time chiming sounds of characteristic tone by using the differential frequency, in which several times of the frequency differential between two frequencies is not coincident with the respective frequencies.

CONSTITUTION: The frequency of a crystal oscillator 1 is fed through a tandem frequency dividing circuit 2 to drive a watch drive motor M. At the same time, the output of the suitable frequency dividing stage FF2 is fed to frequency dividing circuits 3 and 4 so that the circuit 3 effects the division of 1/X whereas the circuit 4 effects the division of 1/Y thereby to generate the frequency-divided signals of frequencies f1 and f2. These outputs are fed to a gate circuit 5 to generate chiming signals of Δf=f2 - f1. In order to generate the chiming sound of characteristic tone, the number of steps of the circuits 3 and 4 are determined so that the several times of Δf are not become equal to f1 and f2. Thus, the chiming signals Δf have the spectrum having signals of unfixed order so that the chiming sounds of such unique characteristic sounds as are not found in the simple sound can be generated.