Because we live in it, it is very easy to forget that "air" has a significant amount of mass. Big boy stuff, like the Yorkville Unity, and even bigger boy stuff, like Funktion One, take advantage of this fact due to their shear size, which yields much better acoustic coupling. It is easy to wiggle a 3" x 5" index card in the air, much harder to wiggle a 4' x 8' sheet of plywood. Can a small, easily portable system produce a 20Hz- 20KHz frequency response? Yes it can. Can a small, easily portable system produce a 20Hz-20Khz frequency response at a reasonably loud level and with low distortion? No, it can not. No matter how hard you blow into a Kazoo, it will never sound like the low note in Bach's Toccata and Fugue in d minor (unless of course the Kazoo was made by Alto and blown by Mix).