BLADE
Flagship Floorstanding Loudspeakers

Now with Metamaterial Absorption Technology

Summary of features

Obsessed with sound quality and committed to bringing a superior listening experience, KEF has been
pioneering innovative acoustic engineering since 1961. In 2009 we gave our engineers free rein to createa speaker to showcase KEF’s technology leadership and powers of innovation with no preconceptions andrestrictions, they came up with the revolutionary Concept Blade – the world’s first Single Apparent Source
loudspeaker. The concept was further refined and developed for production in 2011, when Blade becameHiFi loudspeakers that serious audiophiles could actually own.

• Single Apparent Source technology revolutionises
the orientation of the low, mid, and highfrequency drivers to deliver sound you hear to be
more real and immersive

Blade is an attitude. It’s about exploring the art of the possible and pushing boundaries of HiFi sound without
preconceptions which is why the latest version of Blade benefits from our latest acoustic innovations:
Metamaterial Absorption Technology1 (MAT™), a bespoke 12th generation Uni-Q driver array and a host ofother improvements.
The Blade series consists of two models: Blade One Meta and Blade Two Meta. Both sharing the same DNA,the same technology and the same striking aesthetic, Blade Two Meta is on a slightly smaller scale.

Single Apparent Source Technology
At the heart of Blade lies the Single Apparent Source technology. Single Apparent Source is an extension to
the iconic Uni-Q driver array, the building block of the KEF signature sound. The technology aims to achieve
the acoustic ideal of a point source, where low, mid and high frequencies radiate from one point.
Perfectly calibrated drivers that cover the speaker’s entire bandwidth are configured so all frequencies
appear to radiate from one single point. With Blade, four low-frequency drivers in symmetrically opposing
pairs are tightly packed around a two-way Uni-Q driver where the mid-frequency and high-frequency sharethe same acoustic centre.
The result is noticeably more precise imaging and highly accurate sound across a wider area. This is whatmakes Blade incredibly coherent across all audible frequencies; what you hear is more real and immersive.

Revolutionary sound absorption with MAT™
A truly revolutionary tool in the KEF acoustic armoury, Metamaterial Absorption Technology (MAT) is a highly
complex maze-like structure, where each of the intricate channels efficiently absorbs a specific frequency.
When combined, the channels act as an acoustic black hole, absorbing 99% of the unwanted sound thatcomes from the rear of the tweeter, eliminating the resulting distortion and providing a purer, more natural
acoustic performance.
A result of joint development with the Acoustic Metamaterials Group, using MAT breaks completely new
ground in loudspeaker design, and once again demonstrates KEF’s unrelenting passion for developing newtechnologies to improve your listening experience. Metamaterials are specially developed structures thatuse existing materials in such a way that they exhibit new, desirable properties that are simply not found innaturally occurring substances.

12th Generation Uni-Q with MAT™ delivers
The 12th generation Uni-Q with MAT for Blade is a bespoke driver array engineered to deliver pristine
performance on our flagship loudspeaker. It’s the result of decades of accumulated in-house knowledge andthe application of cutting-edge simulation and analysis tools. The developments are many and all play a partin Blade’s sensational performance.
For starters, the new stiffened aluminium tweeter dome that sits at the centre of the state-of-the-art Uni-Q
driver array is capable of delivering consistently sweet, lucid and lyrical treble, irrespective of the volume.
KEF engineers re-engineered the tweeter gap damper to maximise the space at the back of the tweeter forthe new metamaterial absorber. Optimising the cavity shape and strategically placing two rings of porous
material effectively tame the resonances and imperfections, thus greatly improving detail and clarity.

1 Metamaterial Absorption Technology is a joint development with Acoustic Metamaterials Group.

• Metamaterial Absorption Technology eliminates
99% of high-frequency distortion for pure, naturalsound• Bespoke 12th generation Uni-Q with MAT driverarray for exceptional acoustic accuracy• Two pairs of force-cancelling LF drivers deliverclean, massively extended bass
• Enhanced crossover design fine-tuned the signal
path for maximum clarity• Optimised cabinet design for best acousticperformance• Two models: Blade One Meta, Blade Two Meta
• Available in eight finishes• Customised finishes are available upon request

A new ultra-low distortion midrange motor design uses a copper ring embedded into the motor gap tominimise inductance and variation of inductance with coil position. This lowers the midrange THD andreduces thermal compression, leading to improved efficiency.
The Uni-Q driver array is fully decoupled to prevent unwanted vibrations from muddying the sound. A
new flexible decoupling chassis is designed to reduce vibration and remove coloration. It ensures that any
vibration generated by the mid and high-frequency motor system is not transmitted to the loudspeakercabinet.
A new driver surround is designed to allow longer excursion without causing diffraction and extending
the frequency range of the mid-frequency. Plus, the contours of the dome, midrange horn and surroundare all computer-optimised to ensure a perfectly smooth transition to the cabinet. The patented tangerine
waveguide technology manages the airflow to recreate the wide, even spread of a natural sound field,
dispersing the astonishingly pure high-frequency imaging throughout the room.
The result of these innovations and developments is that this bespoke 12th generation Uni-Q with MAToffers a sound that is more transparent and life-like than previously possible.

Powerful, articulate bass
Blade’s four powerful vented low frequency drivers are perfectly integrated with the 12th generation Uni-Q
with MAT to deliver clean, massively extended immaculately controlled bass. In line with the purity of theoriginal Blade concept, decoupling the voice coil from the diaphragm allows low order crossovers to be used,
for purer, silkier bass response. To avoid exciting the cabinet when playing loud, these drivers are mounted
back-to-back to cancel out kinetic forces that might otherwise colour the output, and each pair occupies aseparate chamber to reduce the need for damping.
In the latest Blade, the crossover design has been enhanced to fine-tune the signal path for maximum clarity.
Plus, two pairs of audiophile-quality WBT connectors allow bi-wiring or bi-amping for lossless transmission.

Performance by design
Blade’s sculptural design is dictated by acoustics. Tapering gracefully from top to bottom and from front torear, the gentle front radius presents no discontinuity to mar sound clarity. Made from an ultra-high density
polyurethane composite, the acoustically inert cabinets’ complex parabolic curves are cleverly engineered toeliminate standing waves that might blur the sound.
Asserting the sophistication of the technology they contain, these stunning speakers are available in apalette of eight finishes, created by blending five cabinet finishes with six Uni-Q® driver cone colours.
You can choose from three high-gloss cabinet finishes with corresponding Uni-Q driver cone colours:
Arctic White/Champagne, Racing Red/Grey, Piano Black/Copper and Piano Black/Grey; or from two mattesatin cabinet finishes with corresponding Uni-Q driver cone colours: Frosted Blue/Blue, Frosted Blue/Bronze, Charcoal Grey/Red and Charcoal Grey/Bronze. If that isn’t enough, customers can also create
their own customised speaker cabinet colour scheme by supplying a Pantone of their choice, fora truly unique Blade.
With the philosophy of innovating in pursuit of the most accurate and realistic sound, Blade is about
perfecting a groundbreaking concept to delight people with the ultimate listening experience.

Arctic White/ChampagneRacing Red/Grey

Piano Black/
CopperPiano Black/
Grey

Frosted Blue/Blue

Frosted Blue/
BronzeCharcoal Grey/Red

Charcoal Grey/
BronzeSpecifications
Model

Blade One Meta

Blade Two Meta

DesignThree-way bass reflex
Single apparent source

Three-way bass reflex
Single apparent source

Drive units

Uni-Q driver array:
HF: 25 mm (1 in.) aluminium dome with MAT
MF: 125 mm (5 in.) aluminium cone
Bass units:
LF: 4 x 225 mm (9 in.) aluminium cone,
force cancelling

Uni-Q driver array:
HF: 25 mm (1 in.) aluminium dome with MAT
MF: 125 mm (5 in.) aluminium cone
Bass units:
LF: 4 x 165 mm (6.5 in.) aluminium cone,force cancelling

Frequency range free field (-6dB)

27 Hz - 45k Hz

30 Hz - 45k Hz

Frequency range typical in roombass response (-6dB)

20Hz

25Hz

Frequency response (±3dB)

35 Hz - 35k Hz

33 Hz - 35k Hz

Crossover frequencies

350 Hz, 2k Hz

450 Hz, 2.2k Hz

Amplifier requirements

50 - 400W

50 - 400W

Sensitivity (2.83V/1m)

88 dB

86 dB

Harmonic distortion 2nd and 3rd
harmonics (90dB, 1m)<0.5% 40 Hz - 100k Hz<0.2% 200 Hz - 2k Hz<0.1% 2k Hz - 20k Hz<0.5% 40 Hz - 100k Hz<0.2% 200 Hz - 2k Hz<0.1% 2k Hz - 20k Hz

Maximum output (SPL)(peak sound pressure level at 1mwith pink noise)

117dB

116dB

Impedance

4 Ω (min. 2.8 Ω)

4 Ω (min. 3.2 Ω)

Weight57.2 kg (126 lbs.)

35.3kg (77.8 lbs.)

Dimensions - with plinth(H x W x D)

1590 x 363 x 540 mm(62.5 x 14.3 x 21.2 in.)

1461 x 338 x 475 mm(57.5 x 13.3 x 18.7 in.)Standard finishes

Piano Black/Copper, Piano Black/Grey, Frosted Blue/Blue, Frosted Blue/Bronze, Charcoal Grey/Red, Charcoal Grey/Bronze, Racing Red/Grey, Arctic White/Champagne
Blade One Meta
Blade Two Meta

1590mm(62.5in.)

1461mm(57.5in.)

363mm(14.3in.)

540mm(21.2in.)

338mm(13.3in.)

475mm(18.7in.)

Visit: KEF.com for more about KEF and its products.

KEF reserves the right, in line with continuing research and development, to amend or change specifications. E&OE.
02.2022 | BLADE