The high-end in-wall speaker market has quietly exploded since the pandemic, as more people turned their living spaces into permanent home theaters and listening rooms. KEF, never one to miss a shift in how we listen, has expanded its Extreme Home Theater lineup with two new models — the Ci5120QLM-THX and Ci3120QLM-THX.
At the core of both models is KEF’s 12th-generation Uni-Q driver array, a hallmark of the brand’s engineering that disperses sound evenly across the room so every listener hears precise imaging and balanced tonality. This latest generation incorporates Metamaterial Absorption Technology (MAT) — a labyrinthine structure that absorbs 99% of unwanted sound from the rear of the tweeter. The result is clearer, more natural treble response and an impressively detailed soundstage that maintains fidelity whether you’re watching films, gaming, or listening to music.
The Ci5120QLM-THX carries THX Ultra certification for large rooms, while the Ci3120QLM-THX is THX Select certified for medium-sized environments — proving that “hidden audio” doesn’t have to mean “hidden performance.”
Each model employs custom-engineered 120mm (4.75-inch) bass drivers with long-throw cones and exceptionally low distortion for deep, controlled bass from compact enclosures.
The Ci5120QLM-THX houses four bass drivers for maximum output, while the Ci3120QLM-THX uses two, optimized for smaller environments. KEF’s Flexible Decoupling Chassis further enhances clarity by reducing unwanted vibration and interaction between the midrange and high-frequency units, while a refined tweeter gap damper improves resonance control.
Both systems are true 3-way designs with fully optimized crossovers, ensuring each driver operates within its ideal frequency range for seamless, full-range sound.
KEF Ci3120QLM-THX: THX Certified Select In-Wall Speaker for High-Performance Home Theater
Since 1961, KEF has been dedicated to reproducing sound exactly as the artist intended — accurate, natural, and immersive. The new Ci3120QLM-THX continues that legacy, combining acoustic innovation from KEF’s premium ranges with the discreet design flexibility that today’s multipurpose living spaces demand.
Part of the brand’s Q Series architectural lineup, the Ci3120QLM-THX is engineered for those who want high-fidelity, room-filling sound without compromising aesthetics. Compact yet powerful, it’s ideal for medium-sized home theaters, living rooms, or hybrid entertainment spaces, offering THX Certified Select performance — a benchmark that ensures the speaker meets strict standards for output levels, frequency response, and distortion.

Two 120mm (4.75-inch) long-throw bass drivers deliver deep, clean low-end response from a compact form factor, while KEF’s Flexible Decoupling Chassis minimizes unwanted vibration for precise midrange and treble performance. A re-engineered tweeter gap damper further reduces resonance, enhancing clarity and detail across all frequencies. With a 3-way system design and fully optimized crossovers, each driver performs at peak efficiency, resulting in an effortlessly cohesive and dynamic presentation.
True to KEF’s “Hide your speakers, not your sound” philosophy, the Ci3120QLM-THX features an Ultra-Thin Bezel (UTB) and a paintable magnetic metal grille for a clean, modern look that integrates seamlessly into any wall. Rated IP64 for dust and splash resistance, it’s equally at home in a wide range of environments — from media rooms to open-plan living spaces.
KEF Ci3120QLM-THX Specifications
| Feature | Details |
|---|---|
| Model | Ci3120QLM-THX |
| Series | Q Series |
| Design Type | 3-Way In-Wall Architectural Speaker |
| THX Certification | THX Certified Select (Medium Rooms) |
| Nominal Impedance | 4Ω |
| Sensitivity (2.83V/1m) | 89dB |
| Frequency Response (±6dB) | 50Hz – 20kHz (open-backed) |
| Frequency Range (-10dB) | 42Hz – 20kHz |
| Max SPL | 105dB |
| Crossover Frequencies | 440Hz, 2.75kHz |
| Drive Units | LF: 2 × 120mm (4.75″) long-throw bass MF: 100mm (4″) Uni-Q HF: 19mm (0.75″) vented aluminum dome with MAT™ |
| Recommended Amp Power | 25 – 250W |
| Recommended High-Pass Filter | 35Hz – 100Hz |
| Nominal Coverage | 150° |
| Mounting Depth | 90mm (3.6″) |
| Cut-Out Dimensions (H × W) | 513 × 163mm (20.2″ × 6.4″) |
| External Dimensions (H × W × D) | 536 × 186 × 96mm (21.1″ × 7.3″ × 3.8″) |
| Ideal Rear Volume | 40L (minimum 20L) |
| Net Weight | 6.2 kg (13.7 lbs) |
| Safety / Compliance | IP64 (splash and dust proof) |
| Ceiling Thickness Range | 6mm – 36mm (0.24″ – 1.42″) |
KEF Ci5120QLM-THX: THX Certified Ultra In-Wall Speaker for Large Home Theater Spaces
The KEF Ci5120QLM-THX represents the next evolution in high-end architectural audio — a solution designed for modern multipurpose rooms where performance and discretion must coexist. Built to KEF’s uncompromising standards, this model delivers cinema-grade sound in a sleek, install-friendly design that disappears into the wall yet fills the room with dynamic, lifelike detail.
For bass duties, the Ci5120QLM-THX features four custom-engineered 120mm (4.75-inch) long-throw drivers with ultra-low distortion, producing deep, articulate low frequencies from a compact footprint. This design, combined with KEF’s Flexible Decoupling Chassis, isolates driver motion to prevent vibration from coloring the sound, while the re-engineered tweeter gap damper enhances overall precision and clarity.

The 3-way system architecture and fully optimized crossovers allow each driver to perform its dedicated role with surgical accuracy. The result is a wide, immersive soundstage that maintains fidelity and dynamics even at high volume levels. Certified as THX Certified Ultra, the Ci5120QLM-THX meets the strictest standards for frequency response, output, and distortion, making it ideal for large home theaters or open-plan entertainment areas where power and accuracy are equally critical.
True to KEF’s design ethos — “Hide your speakers, not your sound” — the Ci5120QLM-THX incorporates an Ultra-Thin Bezel (UTB) and a paintable magnetic metal grille, ensuring a near-invisible finish that blends seamlessly with any interior. Its IP64 rating means it’s protected against dust and splashes, allowing flexible installation across different environments without compromising reliability or performance.
KEF Ci5120QLM-THX Specifications
| Feature | Details |
|---|---|
| Model | Ci5120QLM-THX |
| Series | Q Series |
| Design Type | 3-Way In-Wall Architectural Speaker |
| THX Certification | THX Certified Ultra (Large Rooms) |
| Nominal Impedance | 4Ω |
| Sensitivity (2.83V/1m) | 89dB |
| Frequency Response (±6dB) | 45Hz – 20kHz (open-backed) |
| Frequency Range (-10dB) | 38Hz – 20kHz |
| Max SPL | 105dB |
| Crossover Frequencies | 440Hz, 2.75kHz |
| Drive Units | LF: 4 × 120mm (4.75″) long-throw bass MF: 100mm (4″) Uni-Q HF: 19mm (0.75″) vented aluminum dome with MAT™ |
| Recommended Amp Power | 25 – 250W |
| Recommended High-Pass Filter | 35Hz – 100Hz |
| Nominal Coverage | 150° |
| Mounting Depth | 90mm (3.6″) |
| Cut-Out Dimensions (H × W) | 795 × 163mm (31.3″ × 6.4″) |
| External Dimensions (H × W × D) | 818 × 186 × 96mm (32.2″ × 7.3″ × 3.8″) |
| Ideal Rear Volume | 70L (minimum 35L) |
| Net Weight | 9.7 kg (21.4 lbs) |
| Safety / Compliance | IP64 (splash and dust proof) |
| Ceiling Thickness Range | 6mm – 36mm (0.24″ – 1.42″) |

The Bottom Line
KEF’s new Ci5120QLM-THX ($1,699.99 each) and Ci3120QLM-THX ($1,299.99 each) bring true high-fidelity performance to the in-wall speaker category, combining the company’s 12th-generation Uni-Q driver array, Metamaterial Absorption Technology (MAT), and THX certification for uncompromising accuracy and dynamics. Designed for listeners who want cinema-grade sound without visible hardware, these models are ideal for architectural home theaters, luxury media rooms, and multipurpose living spaces where aesthetics and acoustic precision both matter.
While DALI, Monitor Audio, and Theory Audio Design all make compelling in-wall options in the premium range, KEF’s new offerings stand out for their balanced mix of engineering sophistication, installation versatility, and THX-backed performance. The Ci5120QLM-THX suits larger rooms needing commanding output and low distortion, while the Ci3120QLM-THX fits perfectly into medium spaces where clean detail and immersive sound are the goal.
In short: if you want reference-level sound hidden behind the drywall—and the reassurance that it’s built to exacting standards—KEF’s latest Extreme Home Theater models are among the most complete, future-ready choices in the category.
For more information: us.kef.com/collections/architectural-speakers
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