What is clipping?
In the audio domain, “Clipping” occurs when you push the speakers beyond their capabilities. This is sometimes referred as overload. The reason why this is happening is that there is no limit to the amount of the power that is supplying the amplifier inside the speaker. A normal wave looks like a “ Sinewave “ with smooth edges. After sound clipping, the wave transforms to the “Square Wave“. This is resulting in sound distortion. Aside from that types of the clipping can be hard, soft and limiting.
Hard clipping
It is mainly found in the digital audio domain and it can be explained as this :
Your DAW measures volume levels using a system of decibels relative to full scale (dBFS). 0dB is defined as the topmost point of this scale. It’s as loud as anything can possibly go without becoming distorted. If you push the gain of an audio source up so that its amplitude goes above this 0dB point, the DAW will “clip” off the top portion of the audio’s waveform. The curved top of a sine wave, for example, will be flattened down into a straight horizontal line. This will make it look and sound much more like a square wave. The abrupt juncture between the normal waveform and the clipped portion and the high harmonic frequencies can make the audio sound extremely harsh and fuzzy.
Soft Clipping
This is a milder form of distortion and you can use it as a creative effect on an audio signal. Its timbre is often much less harsh than hard clipping. The result of soft clipping is that increasing input amplitude relates to gradually increasing distortion. This is due to increasing deviation of the shape compared to the original input. There is also potential to change the shape of the soft clipping transfer function shape in order to achieve the range of slightly different distortion characteristics.
Compared to the hard clipping, it avoids this harshness by gently transitioning between the unclipped section of the waveform and the clipped section. When you apply soft clipping to a sine wave, then look at a visual representation of the waveform, the junction between the normal, curved portion of the wave and the flat, clipped portion looks curved. Although there’s still distortion, it’s much less harsh-sounding than it would be if you hard-clipped the signal. It generates fewer high-pitched harmonics than hard clipping does. The gradual transition to the clipped part makes the audio sound much smoother and warmer.
Limiting
Limiting is an altogether much more controlled audio process. Here a loud signal is briefly attenuated, specifically to avoid clipping. The short-term dynamic changes involved introduce a form of distortion, but it is a far more benign form and, again, it is rarely recognized as such. The system is linear up to the limiting level, above which the waveform reduces in amplitude but more or less retains its original shape, and thus remains harmonically intact. The distortion that results is usually negligible.
Additional Resources & Source Texts
https://books.google.rs/books?id=Ui8lDwAAQBAJ&printsec=frontcover&hl=sr#v=onepage&q&f=false
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