soft clipping
Hi there
as a guitarist my answer will probably be very different to others
Clipping is something that naturally occurs in an amplifier, when the amplitude of the electrical signal reaches an unsustainable level, the top section of the signal "clipped", which leaves you with a rather "square" looking signal. This square looking signal can be useful, but if not it can be repaired or rectified by using diodes to "soften out" the signal. leaving you with a signal that has been clipped, and then softened, hence the term soft clipping.
Soft clipping stops the sound becoming overdriven, if for example a guitar amplifier is overdriven i.e. by increasing the gain or volume, it would give the sound you may hear from a rock guitarist for example.
sorry if this is not much help or not what you where looking for