28/02/2014
Though you might not think it, subwoofers are actually shy, retiring types: affordable examples are often hidden behind sofas, while pricier designs are commonly disguised in coffee-table-esque wood and glass. You aren't supposed to notice your subwoofer at all, in fact: both sonically and visually, the best designs are intended to be as ‘invisible' as possible.
But B&W thinks differently. This compact silver sphere is as visually arresting as you'd imagine a subwoofer could ever be. And the styling isn't simply for show: it's a great example of form following function. The declared design aim was “the Holy Grail of subwoofer design: deep and clean bass from a near-invisible box”. So, while you might not believe it, the spherical cabinet was actually created for technical, not marketing reasons.
Here's the science bit: the smaller you make a subwoofer cabinet, the smaller the drive unit has to be. If you want to preserve bass output, you have to compensate with increased power and fancier drive unit technology – but this only increases the already considerable pressures exerted on your small cabinet. The upshot is resonance, caused by distortions of the cabinet's structure under the air-pressure load generated by the driver's movement, and that's bad for sound quality.