At KEF, we believe that music shouldnot just reach your ears, but your heart.
Our passion for music drives our questfor quality sound, and inspires constantinnovation. We develop tools thatdeliver music faithfully and honestly, inall its glory. We believe that everyonedeserves to experience music as it wasmeant to be heard.

The pleasure of sonic perfection

One of life’s great joys is to experience the intensity ofan outstanding recorded performance in your own space.
Q Series speakers by KEF reproduce recordings in highresolution. The sound is natural and accurate, exactly likethe original performance.

The Q Series range, now in its eighth iteration, has longdelighted those who aspire to fine audio. This edition hasbeen extensively redesigned to enhance the depth andclarity of the sound. Within the collection are sets for everyroom, budget and taste.

Acoustic excellence is born this wayThe latest enhancements to Q Series speakers elevate the rangeto new levels of quality and enjoyment. The new system designis characterised by repositioned drivers and ports. Materials andcomponents have been rethought, updated. Potential sources ofdistortion have been eliminated.

At the hear t of the evolved Q Series is the legendaryUni-Q driver array. This signature innovation places thetweeter in the acoustic centre of the midrange and basscone, bringing the acoustic ideal of a single point sourcecloser than ever to realisation.

Expect to hear effor tlessly sharp, clear highs, sweetlyrobust midrange and fast and clean bass with minimumdistor tion at any volume. In shor t, flawlessly accuratereproduced sound.

Tweaking the tweeter

A word about drums and bassThere’s a magnetism in the lower tones. Few can resist the call of a primeval beat echoingfrom the dawn of humanity. For sheer gut-thumping energy, Q Series speakers will notdisappoint. However there’s more to bass than raw power. Much more.
The Q Series faithfully reproduces the subtleties of powerful bass instruments. Feel thetwangy grunt of a round-wound bass guitar string thumped with a plectrum, the baritonebounce of a kettledrum, the multidimensional majesty of Bach blasted through a massivepipe organ. The nuances of these glories are emphasised with the beefier roll surrounds ofthe low frequency drivers and ABRs (Auxiliary Bass Radiators).

Tweeter assembly

Low frequency driver

Auxiliary Bass Radiator

512453After careful consideration and much debate we modifiedaspects of the Uni-Q driver array that is the centrepieceof Q Series speakers. The decisions of our engineerswere informed by computational modelling, followed bymany hours of exhaustive laboratory testing understringent conditions.
Refinements to this generation of Uni-Q driver include adamped tweeter loading tube and a cone neck de-coupler.
The cone neck de-coupler reduces output in the conebreakup region to improve high frequency performance.

The cone return has been removed to further improvebreakup behaviour by reducing mass at the code edge.
1

Damped tweeter loading tube – This reduces anyharshness in the lower treble frequencies by moregently terminating the sound produced from the rear.

2

Cone structure – This innovation reduces conebreakup and improves midrange performance.

3

Suspension – Optimised design allows moremovement, better controlled excursion and lowerdistortion.

4Rubber suspension – Superior to fabric, the newrubber rear suspension allows greater ABR excursionand a lower tuning frequency so that the speaker canplay deeper and louder.

5Roll surround – A larger roll surround allows a longerthrow with less distortion at high sound pressure levels.

Take it from the topA long, tall salutation to KEF traditions,the floorstanders represent the height ofexcellence in the Q Series range. Withineach elegant cabinet are numerousenhancements.

The Uni-Q driver is now isolated within a sealed box. Theenclosure reduces low frequency load on the Uni-Q andthe possibility of intermodulation distortion.
Crossovers are upgraded with low distortion inductors.
The optimised design requires only a single pair ofbinding posts. Elements of the Uni-Q driver, ABR andLF driver are constructed with new materials, which subtlyenhance performance.
To cater to every spatial challenge faced by the audiosystem designer, our floorstanders are available in threesizes. Whether the Q550, Q750 or the Q950 model,a Q Series floorstander speaker set fills a room withastonishing sound of blissful purity.

Optional speaker grilles are available for these speakers.

Compact speaker,expansive soundThe remarkable Q Series bookshelf speakers excel whenspace is limited. In fact the most discerning listener will bepleased by the quality of the sound produced by our juniorfamily members.
To optimise the high resolution sonic image of thesespeakers we repositioned the Uni-Q driver at the centreof the cabinet. This avoids any possibility of standing wavesand reduces resonance within the enclosure. By facing thelow frequency port to the rear we reduce the audibility ofmidrange leakage.
Curious about the possibility of coaxing even more fromthe port, KEF engineers modelled the geometry withcomputational fluid dynamics. This led to a flared port thatminimises turbulence at high levels and reduces port noisewith less low frequency compression.

BeforeAfter – Turbulence has been significantly reduced inthe bookshelf speakers’ CFD-designed portsOptional wall mounting kits and speaker grilles are available for these speakers.

Hear, there andeverywhereA talented modern sound engineer cantake the listener into a rainforest withwildlife above and around... inside theengine room of a doomed steamship...
within the royal box at a Viennese operahouse. We believe such talent deservesto be heard, and go to great lengths toensure that an array of Q Series speakerswill enable true excellence in surroundsound home cinema.

To accurately reproduce a film director’s intention, a centrechannel speaker is essential. Much of the dialogue andsound effects in a movie are recorded to be produceddirectly from the front of the screen. Q Series centrespeakers are engineered to fulfil this.
A Q Series centre speaker will uplift those subtle nuancesof mood and character that define the emotional rangeof the human voice. Within each cabinet is a Uni-Q driverisolated inside its own enclosure to reduce the possibility ofunwanted excursion spillover from the lower frequencies.
Flanking the Uni-Q are a low distortion bass unit twinnedwith an ABR to optimise the home cinema.

A rhapsody in ebony and ivoryUnderstanding that our products will be in use for many years, and verylikely decades, KEF designers seek longevity in style. The sculpted Q Seriesfinish epitomises our approach with seamless, sleek cabinets unblemished byvisible fittings and joins.
Q Series speakers are coated with a fine satin finish in black or white withmatching driver colours. Should you wish to conceal the drivers, optionalmagnetically attached speaker grilles are available. Wall mounting kits are afurther option for the bookshelf models.

Specifications

Model

Q150

Q350

Q650c

Q50a

Model

Q550

Q750

Q950

DesignTwo-way bass reflex

Two-way bass reflex

Two and a half-way bass reflex

Two-way Closed Box

DesignTwo and a half-way bass reflex

Two and a half-way bass reflex

Two and a half-way bass reflex

Drive units

130mm (5.25in.) aluminium Uni-Q 165mm (6.5in.) aluminium Uni-Q25mm (1in.) vented aluminium25mm (1in.) vented aluminiumdome HFdome HF

Drive units

130mm (5.25in.) aluminium Uni-Q25mm (1in.) vented aluminium dome HF130mm (5.25in.) Hybrid aluminium LF2 x 130mm (5.25in.) aluminium ABR

165mm (6.5in.) aluminium Uni-Q25mm (1in.) vented aluminium dome HF165mm (6.5in.) Hybrid aluminium LF2 x 165mm (6.5in.) aluminium ABR

200mm (8in.) aluminium Uni-Q38mm (1.5in.) vented aluminium dome HF200mm (8in.) Hybrid aluminium LF2 x 200mm (8in.) aluminium ABR

Frequency range free field (-6dB)

45Hz - 50kHz

42Hz - 50kHz

38Hz - 33kHz

Frequency response (±3dB)

58Hz - 28kHz

48Hz - 28kHz

44Hz - 28kHz

Crossover frequency

2.5kHz2.5kHz2.2kHzAmplifier requirements

15 - 130 W

15 - 150 W

15 - 200 W

Sensitivity (2.83V/1m)

87dB

88dB

91dB

Maximum output

110dB

111dB

113dB

Nominal impedance

8 � (min.3.5 �)

8 � (min.3.8 �)

8 � (min.3.2 �)

Weight *14.5kg (32 lbs)

16.5kg (36.4 lbs)

20.6kg (45.4 lbs)

Dimensions (H x W x D) *873 x 180 x 278 mm

923 x 210 x 306 mm

1062 x 244 x 328 mm

Dimensions (H x W x D)with plinth *926 x 299 x 310 mm

977 x 323 x 310 mm

1116 x 357 x 328 mm

ColourBlack / WhiteBlack / WhiteBlack / White

165mm (6.5in.) aluminium Uni-Q25mm (1in.) vented aluminiumdome HF165mm (6.5in.) Hybridaluminium LF165mm (6.5in.) aluminium ABR

130mm (5.25in.) aluminium Uni-Q25mm (1in.) vented aluminiumdome HF

Frequency range free field (-6dB)

47Hz - 50kHz

42Hz - 50kHz

55Hz - 50kHz

96Hz - 19.5kHz

Frequency response (±3dB)

51Hz - 28kHz

63Hz - 28kHz

64Hz - 28kHz

105Hz - 18.5kHz

Crossover frequency

2.5kHz2.5kHz2.5kHz2.5kHzAmplifier requirements

10 - 100 W

15 - 120 W

15 - 150 W

10 - 100W

Sensitivity (2.83V/1m)

86dB

87dB

87dB

86dB

Maximum output

108dB

110dB

110dB

106dB

Nominal impedance8� (min.3.7�)8� (min.3.7�)8� (min.4.2�)8� (min.4.6�)Weight *5.6kg (12.3 lbs)

7.6kg (16.8 lbs)

13.6kg (30 lbs)

4.25kg (9.4 lbs)

Dimensions (H x W x D) *303 x 180 x 278 mm

358 x 210 x 306 mm

210 x 629 x 304 mm

174 x 180 x 259 mm

Dimensions (H x W x D)with rubber feet *307 x 180 x 278 mm

362 x 210 x 306 mm

214 x 629 x 304 mm

178 x 180 x 259 mm

ColourBlack / WhiteBlack / WhiteBlack / WhiteBlack / White

Accessories

Q150 Black Cloth Grille

Q350 Black Cloth Grille

Q650c Black Cloth Grille

Accessories

Q550 Black Cloth Grille

Q750 Black Cloth Grille

Q950 Black Cloth Grille

Weight0.15kg (0.33 lbs)

0.2kg (0.44 lbs)

0.4kg (0.88 lbs)

Weight0.5kg (1.1 lbs)

0.6kg (1.32 lbs)

0.8kg (1.76 lbs)

Dimensions (H x W x D)

274 x 173 x 9 mm

330 x 200 x 10 mm

617 x 202 x 9 mm

Dimensions (H x W x D)

845 x 174 x 13 mm

898 x 204 x 10 mm

1035 x 236 x 10 mm

ColourBlackBlackBlackColour

Black

BlackBlack* Measurement per unit