KEF R11 Floorstanding Speakers
Nestled in the centre of these lies the new 12th generation Uni-Q driver array. The 125mm (5 in.) midrange driver and 25mm (1 in.) aluminium dome tweeter combine to deliver an even more natural midrange and treble than believed possible at this price point. The result is a speaker that can pick out the softest details with grace and refinement, as well as deliver raw power and strength.
Derived directly from the Reference Series, the Shadow Flare is an innovative method of reducing harmful cabinet diffraction and one that allows the wonderful Uni-Q to work at its highest level.
Shadow Flare is more than just a trim ring. It is a precision designed surface that extends the waveguide effect of Uni-Q. The tweeter no longer has line of sight of the cabinet edges, creating a ‘shadow region’ at the points where the potential for diffraction is highest, minimising the acoustic impact to negligible levels.
The result is improved clarity, particularly when it comes to the subtle nuances of plucked strings and other percussive sounds.
To maximise bass performance in the new R Series, the dedicated low-frequency drivers are built using a two-part structure, where a shallow concave aluminium skin sits atop a paper cone. This stiffness combined with the cone’s unique geometry reduces additional resonances and delivers the pistonic movement that makes these drivers time so well.
The new drivers also benefit from a completely redesigned magnet system that creates a more even magnetic field, and a design of suspension that reduces harmonic distortion for a cleaner, more precise sound.
The result is tight, agile bass that digs out all the soul and punch available in the low end.
All the cabinets in the new R Series benefit from Constrained Layer Damping bracing. Originally developed for the multiple award-winning LS50, this system utilises internal braces joined to the panels by a lossy interface rather than being adhered to it rigidly. This approach is highly effective at dissipating unwanted vibrations.
A new internal bracing layout works alongside Constrained Layer Damping to create an incredibly inert platform from which the drive units can work their magic, enabling the R Series to deliver music as it is supposed to sound, without any unwanted extras.
Flexible Port Technology
When it comes to generating deep, articulate bass, port design is a vital element.
The ports in the R Series are precisely positioned and feature innovative flexible walls. Using computational fluid dynamics, the flare and profile of each port is calculated to delay the onset of turbulence, while the flexible port walls prevent longitudinal resonances from colouring the midrange.
The result is not only better bass, but cleaner sound further up the frequency range in the vital lower midrange area.
|Design||Three-way bass reflex|
|Drive Units||HF: 25mm (1in.) vented aluminium dome
MF: 125mm (5in.) aluminium cone
LF: 4 x 165mm (6.5in.) hybrid aluminium
|Crossover Frequency||400Hz, 2.9kHz|
|Frequency Range (-6dB)||30Hz - 50kHz|
|Typical in-room Bass Response (-6dB)||26Hz|
|Frequency Response (±3dB)||46Hz - 28kHz|
|Harmonic Distortion (90dB, 1m)||<0.3% 0.3% 120Hz - 20kHz|
|Amplifier Power (recommended)||15 - 300W|
|Nominal Impedance||8Ω (min.3.2Ω)|
|Weight||37.7 kg (83.1 lbs.)|
|Dimensions (H x W x D)
|1249 x 200 x 383.5 mm
(49.2 x 7.9 x 15.1 in.)
|Dimension (H x W x D) with terminal with Plinth||1295.5 x 310.6 x 383.5 mm
(51 x 12.2 x 15.1 in.)
|Finishes||Black Gloss / White Gloss / Walnut|
|Manufacturer Link||KEF R11 Floorstanding Speakers|
|Free warranty||5 years|
|Delivery Time||1 - 5 Working Days|