The amplitude of the wave is bigger to begin with. I think the waves in water analogy is suitable here: drop a stone in water and there'll be very big ripples j

The amplitude of the wave is bigger to begin with. I think the waves in water analogy is suitable here: drop a stone in water and there'll be very big ripples just around the point where it drops, but they'll get smaller the further out they are. Drop an even bigger stone, you'll get bigger ripples. That's power.