Floor Loudspeaker Reviews

You might recall that ditty from childhood about the little engine that could (I think I can, I think I can, I think I can...). It's an apt metaphor for high-end audio. In traversing the aural sepulchers of last winter's Consumer Electronics Show and the summer's HI-FI Show, I routinely encountered one divine sound system after another. Yet while I never tire of transcendent sonics, eventually I become inured to the procession of celestial, cost-no-object speakers. It's like having a white-light experience, then returning to the gritty reality of life on earth, where for most of us cost is not merely the object, but the determining factor in finding an optimal balance among audio components.

People come to high-end audio with different needs and expectations—some fairly reasoned, some slightly more highfalutin. Some listeners want to get as close as possible to an immersion experience, be it of a live performance or of some more idealized studio ecstasy. Others are enraptured by the status and sex appeal of big, hot-rod components, and simply dig gear—much as they might dig the visceral rush of a high-performance car. Still others compulsively upgrade their equipment in search of some unattainable perfection. But no matter the initial motivation, all roads eventually lead back to a love of music.

The story's been often told: 30 years ago, British speaker manufacturer KEF was asked to design a small, spherical loudspeaker that could be used in a European project to research room acoustics. The speaker had to have wide, even dispersion, so KEF's solution was to mount the tweeter coaxially, on what would have been the woofer's dustcap. That "point source" drive-unit, called the Uni-Q, began appearing in KEF's commercial speaker models in 1989, starting with the Reference 105/3—but it wasn't until the appearance of KEF's 50th-anniversary loudspeaker, the LS50, which I reviewed in December 2012, that I felt that the Uni-Q drive-unit had fully fulfilled its promise, at least in a speaker I had auditioned in my own room.

The penultimate stop on Bob Reina's British Invasion Tour of Affordable Loudspeakers (footnote 1) brings us to the doors of KEF. Although KEF is a large and well-established British firm, I've noticed that their product lines have not been as visible in the US as those of, say, B&W, Wharfedale, or Mission. In fact, the last time I heard a KEF speaker, it was the company's then-flagship design, at a Consumer Electronics Show nearly 20 years ago! Before that, when I lived in London, KEFs were ubiquitous, down to the older, entry-level designs tacked to the walls of the ethnic restaurants I frequented. My strongest KEF memory is a cumulative one: Every KEF speaker I've ever heard, regardless of price, venue, or setup, has always produced good, convincing sound.

Planned for KEF's 60th anniversary, much as the LS50 was planned for the company's 50th, the LS60 Wireless is a statement product that encompasses the premise of company founder Raymond Cooke that loudspeaker performance could be improved through the application of new materials and new technologies. Improvements in recent KEF designs include the refinement of the Uni-Q coaxial driver, Metamaterial Absorption Technology (MAT), force-canceling Uni-Core woofers with P-Flex surrounds, cabinets shaped to reduce diffraction, and the configuration and arrangement of drivers to create what KEF calls a Single Apparent Source.

The Model R107 represents the flagship of KEF's Reference Series, and is second only to the Professional Series KM-1 in KEF's product line. Anatomically, the 107 resembles a person. Beneath a decorative "hat," there's a special head assembly akin to the head on the old Model R105. This head assembly contains the brains of the 107, namely a T33 ferrofluid-cooled tweeter and an improved version of the classic B110 midrange driver, featuring a better voice-coil and a new polypropylene cone. The nerve center is also here, in the form of two passive dividing networks and load-impedance equalizing network. Level equalization of the drivers is performed actively within the KUBE, the second brain of the 107—about which you'll hear more shortly.

In the late 1980s, KEF, then as now a leader in bringing new technology to loudspeaker design, developed a unique coincident driver that positioned the tweeter in the throat of the midrange/woofer cone. In a flash of inspiration, they dubbed it the Uni-Q, and the driver immediately not only found its way into the company's more upscale speaker designs, but also became a key element in a major European research project on room acoustics. That study's results appear to have been inconclusive, but the Uni-Q lives on as the defining element of KEF loudspeakers.