























R11
R11 is the flagship of the new R Series range. Boasting four 165mm (6 in.) hybrid aluminium bass drivers, R11 digs deep and retrieves an exceptionally clean and musical low-end performance. 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.
Priced as a SINGLE speaker, please add two to your cart.
Uni-Q Driver Array Developed by KEF in 1988, the Uni-Q driver array acts as a single point source, providing pristine sound across a wider area. The R Series benefits from a new incarnation of this driver array, with advantages over its predecessors that include a new midrange motor system that drastically reduces distortion. Air moving across the minute gaps between Uni-Q’s separate elements creates tiny resonances, but KEF engineers have reduced the impact of these necessary gaps by opening a cavity behind the drivers and adding resonance-absorbing damping material for more precise, purer treble. |
Shadow Flare Derived from the Reference Series, the Shadow Flare reduces harmful cabinet diffraction and allows the Uni-Q to work at its highest level. More than just a trim ring, Shadow flare 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 percussive sounds. |
Low Frequency Drivers The R Series’ dedicated low-frequency drivers have a two-part structure, where a shallow concave aluminium skin sits atop a paper cone. This adds stiffness, while the cone’s unique geometry reduces resonances and delivers the pistonic movement that makes these drivers time so well. The new drivers also have a completely redesigned magnet system that creates a more even magnetic field, and a design of spider that reduces harmonic distortion for a cleaner, more precise sound. |
Cabinet Bracing The R Series benefits from Constrained Layer Damping bracing originally developed for the multiple award-winning LS50, and a new internal bracing layout. This combination brings the R Series closer to the internal structure of the Reference Series, and helps it deliver music as it is supposed to sound, without any unwanted extras. |
Flexible Port Technology KEF engineers computer-modeled the ideal crossover networks before exhaustively auditioning every high grade component, individually and together, to select those with the lowest distortion and the smoothest response. Perfectionism takes time, but the difference is plain to hear. Nothing is overlooked - Reference crossovers are even mounted on separate boards and decoupled from the cabinet walls to minimize vibration and crosstalk. |

Write Your Own Review
Model | R11 |
Design | Three-way bass reflex |
Drive Units | Uni-Q Driver Array: HF: 25mm (1in.) vented aluminium dome MF: 125mm (5in.) aluminium cone Bass Driver: LF: 4 x 165mm (6.5in.) hybrid aluminium |
Crossover frequency | 400Hz, 2.9kHz |
Frequency range (-6dB) Typical in-room bass response (-6dB) |
30Hz - 50kHz 26Hz |
Frequency response (±3dB) | 46Hz - 28kHz |
Harmonic distortion (90dB, 1m) | <0.3% 0.3% 120Hz - 20kHz |
Maximum output | 113dB |
Amplifier power (recommended) | 15 - 300W |
Nominal Impedance | 8Ω (min.3.2Ω) |
Sensitivity (2.83V/1m) | 90dB |
Weight * | 37.7 kg (83.1 lbs.) |
Dimension (H x W x D) with terminal * |
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 |
* Measurement per unit
** KEF reserves the right, in line with continuing research and development, to amend or change specifications. E&OE. **

Review |
“Pleasing presence – sonically and aesthetically – remarkable realism and inter-driver coherence, high value in cost-to-performance arena…there’s a lot to love about the R11’s.” |
Year: 2019 |
Magazine / Issuing Body: the abso!ute sound |
Country of Publication: United States |
Product: R11 Floorstanding Loudspeaker |


Best High-End Speaker 2019-2020 |
KEF has been making great speakers for almost 60 years, but it’s hit a new high in style, performance and value with the new R Series. The R11 brings together all the elements of that success, from the latest generation coaxial Uni-Q driver for superb imaging and focus, anodised to match the choice of premium cabinet finishes, through to the clever microperforated grilles, which solve the old ‘on or off’ problem. The result is a slender speaker capable of a big, rich, room-filling sound packed with detail and delivering superb musical involvement, and with the style to ensure it looks every bit as impressive as it sounds. |
Year: 2019 |
Magazine / Issuing Body: EISA |
Country of Publication: United Kingdom |
Product: R11 Floorstanding Loudspeaker |


Recommended Reference Component |
“KEF’s R Series R11 speaker impressed the heck out of me. First, it’s nice to look at -- a pretty speaker of first-class fit and finish, and color-coordinated from top to bottom. Second, it’s chock full of cutting-edge technological innovation: e.g., the 12th generation of KEF’s Uni-Q driver, Shadow Flare diffraction control, and flexible port linings. But none of that would matter without the third thing: the R11 sounds even better than it looks.” |
Year: 2019 |
Magazine / Issuing Body: SoundStage! Hi-Fi |
Country of Publication: United States |
Product: R11 Floorstanding Loudspeaker |
R Series Brochure | • Open In New Window • Download |
R Series Info Sheet | • Open In New Window • Download |
R Series White Paper | • Open In New Window • Download |