We do drivers

Read any discussion about woofers and you get the impression that distortion as a topic is eagerly avoided. If it is mentioned, it is done sotto voce, implicitly. For instance: “you can’t get good bass out of a small long-stroke driver. There’s no substitute for cone area when you want to move air”. Doesn’t sound like it is about distortion at all, does it? Let’s unpick the statement a bit: there is no substitute for cone area.

Of course there is: displacement. If you want to move 100 cc of air, you could move a 500 cm2 cone by 2 mm or you can move a 200 cm2 cone by 5 mm. At the wavelengths we’re talking about, there’s no difference between the two. So if the bigger driver sounds better, it must be because it’s managing that 2 mm movement much more precisely than the smaller driver is managing its 5mm. And that is a statement about distortion.

Motional feedback addresses the question why a short-stroke driver is more accurate over short strokes than a long-stroke one over long strokes and enables us to build a long-stroke driver that’s just as accurate as a short stroke one for the same acoustical output. More accurate in fact, because once you understand the problem, there’s no reason why you shouldn’t include cone movement into the amplifier feedback loop. By pairing StarBass accelerometer technology with state of the art low note drivers we provide a foundation for systembuilders to create high performance servo bass systems.

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