Kef Uni Q Loudspeakers The Range Catalog

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People who know sound, know KEF. Its a name that commands such respect because weve never been a me too manufacturer. Ever since the early days of hi-fi, our approach has been driven by a passionate belief in the power of new materials, new technologies and design ingenuity to heighten the enjoyment of recorded sound. This is as true today as it was back in 61, when KEF was founded by Raymond Cooke, which is why KEF speakers have ranked among the finest in the world in ever y decade since . In that time , KEF has pioneered many landmark innovations. New dia phragm materials.Neoprene damping.The use of computer modelling in research and quality control. Digital testing to unprecedented tolerances. Total system design methods.Conjugate load network techniques. And arguably the greatest breakthrough of all:the Uni-Q array,based on technology originally developed for the NASA space programme and protected by world wide patents. No other manufacturer has done more to advance the principles of loudspeaker engineering, and none is better placed to exploit the potential of the latest digital formats. Separating out the midrange and high frequency drivers into their own pods has long been a KEF tradition dating all the way back to 1977 with the worlds first speakerto do this, the Model 105. This technology lives on today in the Model 207 flagship. KEF - THE FACTS AND THE FEELING Fresh ideas are what we breathe - but only obsession with detail can make them work Raymond Cooke MBE 1925 - 1996 Founder of KEF KEF Production Facility at Maidstone Model 105 1977-79Model 105/4 1980-82Model 105/21982-87Model 1071986-89Model 107/2 1990-96Model 207 2001 POD TECHNOLOGY

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1 KEF LOUDSPEAKERS What to look for when choosing your speakers Of all the elements in your audio system, changing y our speakers can make the bigg est difference in sound quality. As a rule of thumb , the speak ers in a basic two-channel hi-fi system often account for about a third of the total system cost. Speaker quality has a lot to do with size and the number of drive units; but ultimately what matters is how well they reproduce your kind of music or film soundtrack in your room at the volume you most enjo y. Although technical specifications are helpful, you can only find which model best suits your personal preferences by hearing them in action. These are some of the things you should be looking for... Drive units Hi-fi drivers are dedicated to different parts of the frequency spectrum. Bass units reproduce sound between 20 to 500Hz, midrange drivers (carrying most of the identifying tones of music or speech)usually from 200Hz to 4kHz, and HF drivers (tweeters),from 2kHz to above 20kHz. Long-throw drivers allowa large amount of cone movement, and thereforegenerate higher sound pressure levels. A strong chassis such as cast aluminium provides a rigid platform for the moving coil/cone assembly and avoids the energy being drained from the cone into the cabinet itself. Some form of mechanical decoupling between the chassis and the cabinet can greatly reduce the transmission of this vibrational energy to the cabinet walls. Cone materials vary.Tweeters are usually made from metallic or fabric materials - the former tend to be very revealing and detailed; the latter, a more reserved sound. Components Crossovers act as the brains of a speaker, allocating the various frequency ranges to the appropriate drivers, with filters to stabilise impedance loads and shape frequency response. The quality of the components (such as polypropylene capacitors and air-cored inductors) directly affects acoustic fidelity. Setting up High performance speakers usually have dual sets of connectors (binding posts) and crossovers with separate sections for low and high frequencies. This is to accommodate bi-wiring (using two sets of cables to improve resolution) and bi-amping (in which each set of connectors is wired to a separate amplifier for optimum response across the frequency range). KEFs new Reference Series even features 3 pairs of connectors for tri-wiring or tri-amping. Most speakers sound better after a few hours use. All you have to do then is sit back and enjoy. Imaging Stereo imaging is the illusion of a realistic 3D presence that seems not to come from the speakers themselves, but a virtual sound stage in which different instruments or sound effects are localised. With conventional speakers (as opposed to KEF Uni-Q), this illusion only occurs in a relatively small area - the sweet spot. To test speaker dispersion characteristics, move around the listening area. Does the sound fade as you move away from the main axis of the speaker? Do central images stay centrally located at some frequencies but not others? Measuring perf ormance The smoother a speakers frequency response, the more faithful its reproduction of the audio signal. Transient response is also important, reflecting the speakers ability to respond quickly to any sudden change in the signal without blurring (smearing) the sound. How loudly a speaker plays depends on its sensitivity, maximum output capability and power handling. Low sensitivity speakers require larger amounts of amplifier power to reach a given loudness level. High sensitivity speakers require relatively less and can be used to compensate for low amplifier power. When compensating for low sensitivity speakers remember that a 10dB increase in sound pressure level, which sounds twice as loud, requires 10 times more power. Always look for a wide dynamic range in a speaker - the range of sound intensity that can be reproduced without distortion. Its expressed as a ratio in decibels. In speech, this is rarely more than 40dB; in orchestral works, it can be as much as 75dB. Judge whether loud passages sound appropriately louder than quiet ones. Can you hear subtle changes when something else is playing loud? Does music come to life at high volume, or blur? Ask yourself also whether the sound picture is complete at the frequency extremes. Or has bass, for example, been sacrificed to midrange clarity? Accuracy is a matter of how closely the speaker reproduces live sounds. How much detail can you hear? Do individual images sound separate from each other, or are they like highlights in an acoustic soup? Neutral balance gives the human voice a natural timbre, without distortion at frequency extremes. Listen for colouration - do voices sound strange? Is there too much sibilance? Can you differentiate the sound of similar but different instruments? Or does a violin sound like a viola, a Stratocaster like a Les Paul? SPL( ) FREQUENCY H ) 110 100 90 80 70 60 20 200 k2 k i Re e n e 2 00 FREQUENCY (Hz) 20 200 k Ci Ref 2000 31 6 10 3 16 2k 

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7 Q1 All the benefits of the latest Q Series in a compact speaker with the power to fill the room with big sounds. It has the same Uni-Q driver array as the floorstanding models, reproducing the frequency spectrum with virtually no crossover effects. Genuine performance - and great value. Q2ds The new Q2ds dipole surrounds create the perfect diffuse surround effect, as experienced in movie theatres, by utilising two 165mm (6 1/2) Uni-Q arrays. The addition of a downward firing reflex loaded 130mm (5 1/4) bass driver adds weight to the surround effects. Enveloping you in a rich and spacious soundfield. Providing you with the perfect home theatre experience. Q9c The Q9c centre speaker has the same Uni-Q array for a perfect timbre-match with the rest of the Q Series. Magnetically shielded and bi- wirable, it has the power to enrich your viewing experience compared to any conventionally engineered equivalent. Q8s Slim and compact, Q8s is the two-way closed box rear effects speaker for the Q Series range. Using an identical Uni-Q array to the rest of the range, it reproduces diffuse ambient effects with great accuracy. Full magnetic shielding prevents any interference with nearby electronics, and they can be either wall or shelf-mounted. Q4 A 130mm die-cast chassis houses the long throw cone and coincident mounted 19mm aluminium dome HF unit for true point source reproduction. Combine the excellent offaxis dispersion characteristics of Uni-Q with the magnetic shielding of the driveunits and you get a speaker which is much easier to place in the room and one which alleviates the traditional sweet spot found with ordinary speakers. The new Q4 is a true three way speaker with extended bass output which belies the size of its diminutive cabinet. Q6c By utilizing an identical Uni-Q array in the Q6c centre channel, an even tonal balance is obtained throughout the soundstage when combined with other models in the range. Configured for bi-wiring, as are all the new Q Series products, or even bi-amplification, the Q6c has the power and presence to bring your home theatre to life. Q compact The new Q compact brings unrivalled performance to a small bookshelf loudspeaker by making the outstanding attributes of Uni-Q available at an affordable price. Compact in all but performance.