Harmonic distortion意思

Harmonic distortion refers to the presence of harmonics, or integer multiples of the fundamental frequency, in a signal that was not originally present. In audio systems, for example, harmonic distortion can add overtones to a pure tone, which can change the timbre or character of the sound. Harmonic distortion can be either odd or even, depending on whether the harmonics are at odd or even multiples of the fundamental frequency. Odd harmonic distortion is often considered more objectionable than even harmonic distortion, as it can produce a harsh or unpleasant sound.