Sound of Silence

What you see in the photograph above is a steel ball striking an inch thick piece of one of Wilson Audio’s proprietary cabinet materials—in this case legendary X material. The purpose of this test is not to demonstrate that X material can resist being hit by steel balls; that’s a given. In fact, X material is so rigid, a one inch
board foot could withstand the weight of three F15 fighter jets.

Over the years, Wilson has conducted more research into the sonic properties of various materials than any other loudspeaker company. The original quest was to find the ideal cabinet material. But Wilson’s engineers quickly came to understand a basic acoustic principle: no single material is suited for all loudspeaker applications. The cabinet “wish list” of midrange drivers is fundamentally different from the desires of the woofer.

Each material has its own “sound,” determined largely by three factors: a) the resonant frequency of the material b) its monotonicity (does it ring just one frequency with no overtones?) and c) damping (how long does it ring?). How this impacts (pun intended) the sound of a loudspeaker is an object lesson in the complex interplay of physics, more worthy of a textbook than a magazine ad.

One paradox that has long plagued speaker designers: materials that provide excellent damping are typically soft. Soft cabinets are poor launching pads for the loudspeaker’s drivers. The beauty of modern composites (X material) and laminates (M material) is they can be engineered to be at once rigid and highly damped. All of Wilson’s cabinet materials, including X (which has proven its superiority as a bass cabinet composite) and M (which mates beautifully with midrange drivers), have undergone years of development—from theoretical computer modeling to steel ball tests. The final and most critical experiment is to listen to each material in blind comparisons. No matter how good a material looks on paper, it must ultimately possess the rare ability to convey musical beauty.

Even then, the process isn’t done. The restless quest for perfection at the heart of the culture at Wilson Audio dictates that the search for new and better materials is never done. So if you ever have the opportunity to visit the Wilson facilities, don’t be surprised if you hear, from behind a closed laboratory door, the faint sound of a steel ball hitting a solid object.