Now, a perfect speaker should translate that 'step' into a simple, sudden compression of the air in the room. But, because all real world speakers have low frequency limitations, the ideal behavior will look like the graph below labeled "Acoustic Output of Time Coherent Speaker".  You can see how the drivers move as they do a nice job of reproducing the step input signal. A simple first order crossover combines with proper acoustic alignment of the drivers via a slanted baffle to precisely recreate the input waveform.