Can anyone tell me what an amplifier sounds like when it clipps? I have heard the term before but I have never heard an Amp do it. Any Amps I heard usually started sounding poorly before anything weird happened.

you will hear clipping when your tweeter starts to make a very harsh, high, distorted sound.

If you have a stock car stereo, crank it up all the way. Notice how it's heavily distorted and kind of painful? That's clipping.

ya, that's bad midrange or woofer clipping.

it's like listening to speakers with towels over the drivers and mud in the air flow ports while playing it at the highest volume level possible... don't try this, i'm just assuming that would sound like clipping.