KEF Audio Uni-Q manual Behind the cone

The continuing evolution of KEF’s legendary Reference Series has always been based on the concept of benchmark precision. Every time a new generation of models is developed to incorporate more sophisticated technologies, we build prototypes that are as close to perfection as possible.

These then become the ‘Reference’ to which every single production version must conform, each set assembled by a skilled craftsman who matches their performance to a tolerance of just 0.5dB.

As the latest incarnation of this approach, the Reference Series is a quantum leap forward in audiophile quality sound. In fact, its performance envelope extends well beyond the range of human hearing.

This is not as futile as it may at first sound - whereas conventional CDs carry no audio information beyond 20kHz, extended bandwidth formats such as SACD and DVD Audio contain signals up to 40kHz and more. Consider the analogy that even though no-one drives at 200 mph, cars that are engineered to do so are inherently better performers at lower speeds.

That’s why all new Reference series models come with a state of the art 19mm (3/4”) titanium dome HypertweeterTM for massively extended HF performance. Mounted in low diffraction, chrome-plated steel enclosures time aligned with the main array,they deliver flat response to 55kHz and useful energy up to 80kHz. What you hear is a sweeter, more natural sound.

Radical new Uni-Q driver arrays - the ultimate refinement of KEF’s trademark technology - where the tweeter is mounted at the acoustic centre of the midrange cone - provide an immaculate single point source, the Holy Grail of loudspeaker design. With the midrange cone and surround integrated into a single Uni-Form moulding, there are no discontinuities to distort the HF energy from the 25mm (1”) elliptical profile titanium dome tweeter.

With only midrange frequencies to handle, movement of the Uni-Q cone is so modest that virtually no distortion is caused by intermodulation with the tweeter.Like the bass drivers, an open chassis design - minimises acoustic reflection

behind the cone.

The result is an even more spacious, better defined sound stage over a very large area, with exceptional off-axis response and none of the ‘sweet spot’ limitations of conventional speakers.

Bass extension is equally stunning, thanks to ultra-low distortion motor systems and high tech reinforced diaphragms. And with each bass driver radiating directly from its own separate internal enclosure to avoid the distorting effects of vertical standing waves that tall cabinets usually suffer from,

you experience noticeably clearer, more open bass.

As you would expect from a handmade KEF product, build quality is as outstanding as the specification of each individual component. Carefully graded and soldered by hand, KEF’s own oxygen-free copper cable ensures the best possible signal transmission, with terminals machined from solid brass and plated in gold. High order crossovers with advanced air-cored inductors and polypropylene capacitors

ensure faultlessly smooth integration.

For optimum performance in real rooms, all models accommodate tri-wiring and are fitted with a boundary control device to adjust bass response according to speaker positioning and the acoustics of the listening area. Magnetic shielding ensures trouble-free positioning in home theatre applications.

Engineered from laminated birch ply using KEF’s own internal bracing system, the new curved section cabinets are elegantly profiled to minimise colouration and finished in a choice of hand-matched hardwood veneers.

More than ever before, these are very special speakers indeed.

2