Heat. Assuming that is that you're clipping a waveform that is already existing.
However, clipping usually occurs because an energy source is incapable of supplying the full energy required to produce a full, clean wave. In other words, low-powered amplifiers clip the waveform because they can't produce the voltage/current required.
That's why (say) a 200 watt hifi amp doesn't produce a 'louder' sound than a 5 watt amp, but gives a 'cleaner' sound because all of those little high-energy transients don't get clipped off.
However, clipping usually occurs because an energy source is incapable of supplying the full energy required to produce a full, clean wave. In other words, low-powered amplifiers clip the waveform because they can't produce the voltage/current required.
That's why (say) a 200 watt hifi amp doesn't produce a 'louder' sound than a 5 watt amp, but gives a 'cleaner' sound because all of those little high-energy transients don't get clipped off.