KEF iQ1 User manual

Redesigned magnet structures. New, state-of-the-art voice coils. Higher specification components. More rigid chassis and
cabinets. The result of all these innovations is plain to hear. Power handling and sensitivity are better than ever. iQ plays loud
and true, with even clearer vocals than its illustrious predecessor. Even gutsier and more tightly controlled bass. And of course
the impeccable extended bandwidth response you need to get the most out of the latest digital audio and home theatre formats.
As everymodel in the range is voiced for a perfect tonal match, the 3-D soundscape is so seamlessly integrated that everyone
in the room gets the full benefit, wherever they sit.
Acoustic intelligence - that’s the best way to describe what KEF engineers have applied to create a new range worthy of the
award-winning Q Series it replaces. Hence the name: iQ.
From the second you spot the soft sheen of titanium on the main driver cones, you know you’re in for something special.
And you won’t be disappointed.
Because we’vetaken a long, hard look at the inherent advantages of KEF’s trademark Uni-Q®technology - consistentlydetailed
imaging and unrivalled off-axis response - and improved it in dozens of ways.
With newcone materials and surrounds.

SECOND HARMONIC DISTORTION
comparison of response at crossover frequency
comparison of Faraday ring effect
Acoustic intelligence
You don’t have to be a genius to understand why Q Series speakers sound so good. After all, they incorporate
the Uni-Q technology originally designed for one of the world’s finest speaker ranges, KEF’s legendary
Reference Series.
The Uni-Q concept is based on using aerospace materials to make the tweeter small enough to
place at the acoustic centre of the bass/midrange cone. With both drive units on exactly the same
axis and sharing the same waveguide, they behave as a single point source that projects a more
natural sound image over a much larger area than the usual tiny ‘sweet spot’.
This is because the Uni-Q configuration eliminates the inherent problems of having the separate
midrange and high frequency drive units of a conventional speaker. As loudspeaker radiation
varies according to frequency, LF and HF drivers have intrinsically different radiation patterns
whose directivity - known as ‘Q’ - changes at the crossover frequency. Interference (or ‘lobing’)
between the two units causes a dip in power response around this frequency, with a peak above
it due to their differences in directivity. These factors introduce colourations that muddy the
sound image. You get no such problems with Uni-Q. Being coincident and perfectly time-aligned,
the directivity of both LF and HF units is controlled bythe profile of the midrange cone, with no
possible path or phase differences between the two, and no ‘lobing’ interference at the crossover.
The ‘Q’ is unified, in other words - hence the name.
So instead of narrowing towards the crossover and then widening again as is the case with
separate drive units, the Uni-Q radiation pattern remains stable. Power response is uniform,
with smoother variations on and off-axis. The acoustic image is better balanced and more natural
sounding across both direct and reverberant fields. Multi-channel imaging is noticeably clearer and
more accurate.
The Uni-Q array in the Q Series incorporates a sophisticated new tweeter with an aluminium
dome that increases the break-up resonance to 34kHz (as compared to the 25kHz threshold
of a typical standard dome). The MF voice coil is of copper-coated aluminium ribbon,
expensively edge-wound over a polyimide former to increase sensitivity by maximising the amount
of copper in the magnet gap.
The chassis are of precision-cast aluminium for greater rigidity, with a vented design to improve
power handling. The tall profile cone surrounds are of butyl rubber to allow greater excursion,
and therefore higher output. Faraday rings are incorporated into the ultra-low distortion
motor,further reducing harmonic distortion by as much as 20dB. And audiophile-grade
crossovers are connected to the shrouded bi-wirable terminals to ensure the cleanest possible
signal transmission.
With refinements like these, no wonder the sound is so open and natural. No wonder the action
on screen suddenly becomes more compelling. No wonder you get so utterly immersed in the
listening experience. It’s what Q Series is all about.

Black Ash
Dark Apple
Maple
Brand newWalnut and Silver finishes are available subject to special order in certain markets.
Smart thinking
With so much high-end technology inside, it’s not surprising that the Q’s distinctive styling bears a family
resemblance to the latest Reference Series, with the Uni-Q ‘pod’ faired in to elliptical-section cabinets.
The design was driven by functional considerations rather than aesthetics.
Curved enclosures minimise distortion from the internal acoustic reflections generated by parallel straight
surfaces - but because they’re complicated to make, the benefit is usually reserved for the most expensive
audiophile speakers.
QSeries cabinets are thermally formed in ‘heavy’ MDF, whose density makes it acoustically inert to reduce
unwanted colouration of the sound image. Using laminated construction techniques, with inner and outer
layers bonded to a segmented core in a giant press, the precisely radiused panels are exceptionally rigid,
with the Uni-Q arrays faired in to the cabinet. Massive internal bracing tailors the volume of each enclosure
to the exact parameters of its drive unit and minimises any residual panel resonance.
All models have two pairs of fully shrouded terminals for bi-wiring or bi-amplification, and are magnetically
shielded to prevent interference with other electronics.
As you’d expect, the standard of finish is exemplary, with a choice of classic Black Ash, Dark Apple and Maple -
asilky contemporarygrain found on no other range.

Acompact full range floorstander, the iQ5 is a true three-way speaker.
With KEF’s new 130mm (51⁄4”) long-throw LF driver delivering superbly defined bass,
the midrange driver of the 130mm (51⁄4”) Uni-Q point source array is dedicated to
reproducing midrange frequencies with even greater clarity. High order crossovers
ensure seamless transitions between each driver, and with Uni-Q’s remarkable off-axis
dispersion characteristics, you get a speaker that’s as easy to place as it is rewarding to
hear - especially for enjoying the richness and complexity of modern digital formats.
Ideal for use with iQ1 and iQ2c in a home theatre system, it’s a superbly assertive
performer for the modest size of its slender cabinet and outstanding value if you aspire
to genuine audiophile standards of sound reproduction.
The newiQ1 proves that with the right technology, you don’t need big boxes to enjoy
audiophile quality sound.
If you want to create a rich, expansive soundscape in a smaller room without compromising sonic accuracy, it
delivers the full benefit of KEF’s latest design thinking. With the sophisticated new 130mm (51⁄4”) Uni-Q
coincident driver array in a compact reflex-ported cabinet, you experience stunningly clear vocals, fluid midrange
and an unusually spacious 3D sound image no matter where you sit. Being magnetically shielded like the rest of
the range,they’reas easy to place as they are to drive. Everything from the titanium surface of the Uni-Q cones
to the shrouded bi-wire terminals says ‘quality’ - and for music or movies, that’s exactly how iQ1 sounds.
For even fuller presentation where the available space nevertheless dictates a bookshelf speaker,
iQ3 takes all the performance advantages of the iQ1 a step further.
Aslightlylarger cabinet houses KEF’snew generation 160mm (61⁄2”) Uni-Q array, complete with
its acclaimed 19mm (3⁄4”) aluminium dome neodymium tweeter. It’s uncannily good at reproducing
all the subtleties of the human voice, and creates a consistently accurate sound image over an
exceptionally wide area. Musical, efficient and virtually distortion-free, it reveals more detail in your
favourite tracks and brings screen action morevividlyto life.

Breathtaking is the only word to describe it.
Hearing the iQ9 in action takes you to a different place - the illusion of presence is
phenomenal. This awesome full size bass reflex floorstander partners the latest 160mm (61⁄2”)
Uni-Q mid/HF arraywith a brace of potent newgeneration LF drivers featuring ultra-low
distortion motors and natural fibre-loaded paper cones. Impeccable vocals, delicious
midrange and incredible bass extension - and with KEF’smassive internal bracing, none of the
LF distortions that usually affect tall speakers. For orchestral, big band or compositionally
intricate works, we’re talking devastating accuracy and emotional power.
And when complemented by the iQ6c and either iQ3 or iQ7 rear channel speakers, iQ9 is a
formidablycompetent full bandwidth front speaker for large room, high-end home theatre.
Afull bandwidth three-way floorstander that packs real punch, iQ7 floods even the
largest room with an intricate and intensely physical 3D soundscape.
The spec says it all: a new generation Uni-Q point source array with our latest
aluminium dome tweeter at the centreof the matching titanium-coated 160mm (61⁄2”)
cone, partnered by a dedicated long-throw bass driver of the same size. Response is
accurate and distortion-free at all volumes, with fluidly articulate midrange, generous
bass extension and faultless 3-D imaging. The tonal match is perfect with the rest of
the range, and the shrouded terminals are designed for bi-wiring or bi-amplification.
Spine-tingling home theatre has never been more affordable.

Powered Subwoofers
As the lower frequencies play such a big part in recreating the 3-D soundscape encoded in digital formats,
your choice of subwoofer is critical - especially if you want to enjoy the level of sonic immersion you experience
in a modern cinema.
PSW2500
With a high efficiency 250W on-board amplifier driving a 250mm (10") down-firing
woofer, PSW2500 has the power to deliver heavyweight bass effects without
sacrificing clarity. With ground lift switching and movie/music modes,output is easily
adjustable to match the main speakers and room acoustics. The elliptical-section
cabinet is massively internally braced to eliminate unwanted internal resonance,
and finished in Black, Dark Apple or Maple to complement the rest of your
QSeries system.
PSW3500
When you have a 300-watt internal power amp driving a 300mm (12”) long-throw
woofer through audiophile grade circuitry, you expect the earth to move.
KEF’s PSW3500 does just that, anchoring the soundscape in a huge, all-enveloping and
perfectly controlled bass presence. Output, phase and frequency are fully adjustable
to your personal preferences via infrared remote, with a separate sensor that allows
you to place the unit completelyout of sight. Aprodigious acoustic performer with
the power to keep you on the edge of your seat, it’s an investment in pure pleasure.
The pleasures of home cinema depend largely on the quality of your centre channel
speaker. This is an area where the unrivalled dispersion characteristics of KEF Uni-Q
technology make a real difference - the 130mm (51⁄4”) Uni-Q array in the iQ2c projects on-screen
dialogue with equal clarity and realism throughout the room. Configured for bi-wiring or even
bi-amplification likeall the Q Series, its smooth midrange and fast transient attack delivers the listening
enjoyment of high-end audio technology at a surprisingly modest price.
If you’re really serious about home entertainment, iQ6
is the way to go. With the same 130mm (51⁄4”) Uni-Q
point source array flanked by two equally large
long-throw,ultra-lowdistortion LF drivers,it combines the startling vocal clarity of KEF’s latest aluminium dome
19mm (3⁄4”) tweeter with clean, tightly controlled bass extension and high output. Screen action is precisely
located in a denselytextured 3-D soundscape that envelops everyone in the room.
Eloquent, authoritative and deeply involving, it touches the parts other centre channels simply can’t reach.
As the dipole rear effects speaker for the Q Series, the two 130mm (51⁄4”) Uni-Q arrays in
the heavilybraced curved cabinets of the iQ8ds disperse atmospheric effects encoded in
digital soundtracks evenly throughout the listening area to create a sense of place so real
you can almost touch it. Perfectly timbre-matched to the rest of the range, transitions are
seamless and the detailing is impeccable.
Asimple keyhole mounting system allows effortlessly quick wall installation. Sit back and enjoy.

Design Three-way bass reflex
Drive units 2 x 165mm (61⁄2”) LF
165mm (61⁄2”) Uni-Q
19mm (3⁄4”) aluminium dome HF
Frequency response 38Hz - 40kHz
Crossover frequency 250Hz - 2.8kHz
Amplifier requirements 15 - 200W
Sensitivity (2.83V/1m) 91dB
Maximum output 113dB
Nominal impedance 8Ω(min 3.2Ω)
Magnetic shielding Yes
Weight 16.6kg (36.6lbs)
Dimensions 942 x 220 x 327 mm
H x W x D 37 x 8.7 x 12.9 in.
Design Two-way bass reflex
Drive units 130mm (51⁄4”) Uni-Q
19mm (3⁄4”) aluminium dome HF
Frequency response 70Hz - 40kHz
Crossover frequency 2.8kHz
Amplifier requirements 10 - 100W
Sensitivity (2.83V/1m) 89dB
Maximum output 109dB
Nominal impedance 8Ω(min 3.2Ω)
Magnetic shielding Yes
Weight 4.7kg (10.3lbs)
Dimensions 165 x 418 x 220 mm
H x W x D 6.5 x 16.4 x 8.7 in.
Design Three-way bass reflex
Drive units 2 x 130mm (51⁄4”) LF
130mm (51⁄4”) Uni-Q
19mm (3⁄4”) aluminium dome HF
Frequency response 65Hz - 40kHz
Crossover frequency 280Hz - 2.8kHz
Amplifier requirements 15 - 150W
Sensitivity (2.83V/1m) 90dB
Maximum output 111dB
Nominal impedance 8Ω(min 3.2Ω)
Magnetic shielding Yes
Weight 8.9kg (19.6lbs)
Dimensions 165 x 512 x 255 mm
H x W x D 6.5 x 20.1 x 10 in.
Design T
wo-wayclosed box
Driveunits 2 x 130mm (51⁄4”) Uni-Q
2 x 19mm (3⁄4”) aluminium dome HF
Frequency response 65Hz - 40kHz
Crossover frequency 2.8kHz
Amplifier requirements 10 - 100W
Sensitivity (2.83V/1m) 83dB
Maximum output 103dB
Nominal impedance 8Ω(min 3.2Ω)
Magnetic shielding No
Weight 5.2kg (11.5lbs)
Dimensions 180 x 360 x 175 mm
H x W x D 7.1 x 14.2 x 6.7 in.
Design Closed Box, downward firing
Drive units 300mm (12”) ultra long-throw
bass driver
Frequency response 30Hz - 250Hz
Crossover frequency Variable/LFE
Amplifier requirements 300W built in
Sensitivity (2.83V/1m) 100mV for full output
Maximum output 110dB
Nominal impedance N/A
Magnetic shielding Yes
Weight 22.5kg (49.6lbs)
Dimensions 450 x 600 x 395 mm
H x W x D 17.7 x 23.6 x 15.6 in.
Specifications
Design Two-way bass reflex
Drive units 130mm (51⁄4”) Uni-Q
19mm (3⁄4”)aluminium dome HF
Frequency response 50Hz - 40kHz
Crossover frequency 2.8kHz
Amplifier requirements 10 - 100W
Sensitivity (2.83V/1m) 88dB
Maximum output 108dB
Nominal impedance 8Ω(min 3.2Ω)
Magnetic shielding Yes
Weight 4.5kg (9.9lbs)
Dimensions 301 x 175 x 261 mm
HxWxD 11.8 x 6.9 x 10.3 in.
Design Two-way bass reflex
Drive units 165mm (61⁄2”) Uni-Q
19mm (3⁄4”) aluminium dome HF
Frequency response 45Hz - 40kHz
Crossover frequency 2.8kHz
Amplifier requirements 15 - 120W
Sensitivity (2.83V/1m) 89dB
Maximum output 110dB
Nominal impedance 8Ω(min 3.2Ω)
Magnetic shielding Yes
Weight 6.7kg (14.8lbs)
Dimensions 365 x 220 x 327 mm
H x WxD 14.4 x 8.7 x 12.9 in.
Design Three-way bass reflex
Driveunits 130mm (51⁄4”) LF
130mm (51⁄4”) Uni-Q
19mm (3⁄4”) aluminium dome HF
Frequency response 43Hz - 40kHz
Crossover frequency 280Hz - 2.8kHz
Amplifier requirements 15 - 130W
Sensitivity (2.83V/1m) 88dB
Maximum output 109dB
Nominal impedance 8Ω(min 3.2Ω)
Magnetic shielding Yes
Weight 10.2kg (22.5lbs)
Dimensions 815 x 175 x 261 mm
H x WxD 32 x 6.9 x 10.3 in.
Design Three-way bass reflex
Drive units 165mm (61⁄2”) LF
165mm (61⁄2”) Uni-Q
19mm (3⁄4”) aluminium dome HF
Frequency response 40Hz - 40kHz
Crossover frequency 250Hz - 2.8kHz
Amplifier requirements 15 - 150W
Sensitivity (2.83V/1m) 90dB
Maximum output 111dB
Nominal impedance 8Ω(min 3.2Ω)
Magnetic shielding Y
es
Weight 14.5kg (32.0lbs)
Dimensions 865 x 220 x 327 mm
H x WxD 34 x 8.7 x 12.9 in.
Design Closed Box, downward firing
Driveunits 250mm (10”) ultra long-throw
bass driver
Frequency response 33Hz - 150Hz
Crossover frequency Variable
Amplifier requirements 250W built in
Sensitivity (2.83V/1m) 100mV for full output
Maximum output 108dB
Nominal impedance N/A
Magnetic shielding Yes
Weight 14.5kg (31.9lbs)
Dimensions 360 x 495 x 325 mm
H x WxD 14.2 x 19.5 x 12.8 in.

KEF Audio (UK), Eccleston Road,Tovil, Maidstone, Kent, ME15 6QP U.K. Telephone: + 44 (0) 1622 672261. Fax: + 44 (0) 1622 750653 www.kef.com
KEF America, 10 Timber Lane, Marlboro, New Jersey, 07746 USA. Telephone: + 1 732 683 2356. Fax: + 1 732 683 2358 www.kefamerica.com
GP Acoustics GmbH, Heinrichstraße 51, D-44536 Lünen, Deutschland. Telephone: [phone]. Fax: [phone]. www.kefaudio.de
PL1610EN
©KEF Audio (UK) 2005
www.kef.com/iq
KEF and Uni-Q are registered trademarks. Uni-Q is protected under GB patent 2 236929. US patent 5,548,657. Worldwide patents pending.
KEF Audio reserve the right, in line with continuing research and development, to amend or change specifications.