.In tuned amplifiers, harmonic distortion is
Answers
Harmonic distortion can be explained as any distortion or corruption in the output waveform due to the generation of harmonics. The integer multiples of a fundamental frequency are called harmonics.
Although distortion can be defined as any alteration in the waveform of an audio signal, the kind of distortion we're usually talking about in audio is harmonic distortion, which you see cited in amplifier specs as THD, or total harmonic distortion.
Harmonic distortion in amplifiers is usually caused by the amplifier needing more voltage than its power supply can provide. It can also be caused by some part of the internal circuit (usually the output transistors) exceeding its output capacity. Thus, instead of reproducing the peaks of an audio waveform, the amplifier clips them off, hence the term "clipping."
Distortion in power amplifier
In the above figure you can see that every point in the input waveform (waveform1) is exactly reproduced in the non distorted output (waveform2) and the falling edges of the input waveform are unfaithfully reproduced in the distorted output (waveform 3).
