The sound will be distorted and dynamically depressed. The sound will distort on louder transients such as a dynamic drum solo. If the amplifier is driven into clipping on loud transients, you may even hear a "snapping" sound. The snapping is the speaker reproducing an improperly formed sine wave, The snapping or consistent clipping can and likely will damage your speakers!!
Audio Axiom: You can never have TOO MUCH power!
Audio Axiom: You can never have TOO MUCH power!