Cambridge Audio has spent decades building a reputation on a specific philosophy the company calls "Great British Sound," a design language rooted in low distortion, wide bandwidth, and a refusal to editorialize the signal. From the Azur integrated amplifiers to the Edge flagship series and the CX streaming components, the through-line has always been engineering restraint paired with genuine measurement rigor. The L/R X sits at the top of the active loudspeaker world for the brand, a fully powered, fully networked stereo pair that folds a streamer, DACs, amplifiers, and phono stage into two cabinets. For the enthusiast, this is a system in a box, and the interesting part is how many discrete boxes it quietly replaces.
What exactly is the Cambridge Audio L/R X?
The L/R X is a matched pair of active, powered, streaming stereo speakers positioned as a flagship, meaning each cabinet contains its own amplification, digital conversion, and connectivity rather than relying on an external amp. You buy them as a left and right pair, designated L and R, and together they form a complete source-to-driver signal chain. The design intent is to eliminate the amplifier and speaker matching guesswork that defines passive systems. Because the amplifier is engineered specifically for the drivers it feeds, the crossover behavior, damping, and gain structure can be optimized in ways a passive speaker and generic integrated amp cannot easily replicate.
Amplification and Signal Topology
How much power does the L/R X produce and how?
Each speaker delivers 400 watts, for 800 watts total across the pair, using Class D amplification. Class D is the correct choice for an active speaker of this form factor because it runs efficiently and cool, which matters enormously when you are packing amplifier boards, a power supply, DAC circuitry, and a streaming platform into a cabinet only 200 x 330 x 260 mm. A traditional Class AB design would waste much of that energy as heat, demanding large heatsinks that simply do not fit. Modern Class D output stages switch at high frequencies and use output filtering to reconstruct the audio waveform, and contemporary implementations have largely closed the historical gap in distortion and high-frequency linearity that once plagued the topology.
Why does active amplification matter for sound quality here?
Active amplification means each driver, or driver group, is fed by a dedicated amplifier channel after the crossover, rather than a single amp pushing through a passive crossover network. In a passive speaker, the crossover sits between the amplifier and the drivers, dissipating power in resistors and inductors and interacting unpredictably with the speaker's impedance curve. In an active design, the crossover is applied at line level in the digital or analog domain before amplification, so it can use precise filter slopes without the losses and phase anomalies of large passive components. The practical benefit is tighter driver control, better transient response, and a crossover that behaves exactly as designed regardless of program material.
Drivers and Acoustic Design
What driver configuration does each L/R X speaker use?
Each cabinet carries one 28mm tweeter, two 5 inch woofers, and two 6 inch side-mounted force-cancelling passive radiators. The two 5 inch woofers flanking the tweeter form a vertical array, an arrangement that behaves acoustically like a larger effective radiating area while keeping the horizontal dispersion controlled. This layout narrows the vertical lobing and helps stabilize the stereo image, so the sound stays coherent as you move around the room. The 28mm tweeter handles the top octaves and, at 24 kHz on the upper end of the response, extends comfortably beyond the audible band, which supports low phase distortion within the range you actually hear.
What do the side-mounted force-cancelling passive radiators do?
The two 6 inch passive radiators on the sides of each cabinet extend low frequency output without the port noise of a vented design, and their force-cancelling arrangement neutralizes cabinet vibration. A passive radiator is an undriven diaphragm tuned by its own mass that moves in sympathy with the pressure changes inside the sealed cabinet, effectively adding bass extension that a small enclosure could not otherwise achieve. By mounting them on opposite sides so they move in equal and opposite directions, the mechanical reaction forces cancel each other out. The audible payoff is cleaner bass with less cabinet coloration and less energy transmitted into the surface the speaker rests on, which reduces smearing of the midrange.
How low does the L/R X actually reach?
The frequency response is rated at 35 Hz to 24 kHz plus or minus 3 dB, which is genuinely deep for a cabinet this size. That plus or minus 3 dB window is the meaningful part of the specification, because a response figure without tolerance is close to useless. It tells you the 35 Hz bottom end is real and usable, not a marketing number measured at a steep rolloff. Reaching 35 Hz means most acoustic bass, kick drum fundamentals, and the lower registers of synth and organ material are reproduced with authority, and the force-cancelling radiators are what make that extension possible from such a compact enclosure.
Digital Platform, Conversion, and Streaming
What streaming platform runs the L/R X?
The L/R X runs on StreamMagic Gen 4, Cambridge Audio's fourth generation network platform, and carries Hi-Res Audio certification. StreamMagic is the same architecture family that underpins the brand's dedicated network players, and Gen 4 represents its most mature implementation. The platform handles the network stack, service integration, and playback management, and because it is built in-house, Cambridge Audio controls the software lifecycle and update path directly. Hi-Res Audio certification confirms the system can process and reproduce high-resolution files rather than downsampling everything to CD resolution.
Which streaming services and protocols are supported?
The L/R X supports AirPlay 2, Chromecast built-in, Roon Ready, Spotify Connect, Tidal Connect, Qobuz Connect, and Amazon Music, over dual-band Wi-Fi. This is an unusually complete list, and the significance is that it covers nearly every casting and native-app ecosystem an enthusiast might already live in. Roon Ready certification matters most to the serious listener, because it means the speakers integrate as endpoints in a Roon environment with bit-perfect delivery and proper metadata handling. Tidal Connect and Qobuz Connect keep playback in the native apps of the two most audiophile-oriented streaming services, avoiding the transcoding compromises of casting.
How do you control the L/R X without a display?
There is no onboard display, so control comes through the StreamMagic app, a Bluetooth Low Energy remote, and underlighting that provides visual feedback. The decision to omit a screen keeps the front baffle clean and avoids the light pollution and clutter a display introduces into a listening room. The BLE remote handles quick tactile adjustments, while the app manages source selection, streaming, and configuration. The underlighting communicates status such as source changes and volume at a glance, functioning as a minimalist indicator rather than an information display.
Connectivity and System Integration
What can you plug into the L/R X?
The input roster covers HDMI eARC, optical TOSLINK, RCA line, Moving Magnet phono, USB-C audio, USB-A media, and Bluetooth, with no coaxial digital input. This breadth is what makes the L/R X function as a system hub rather than just a speaker. HDMI eARC lets it serve as the audio engine for a television, receiving high quality multichannel-capable audio over a single cable and supporting CEC volume control from a TV remote. The optical input handles legacy digital sources, and the RCA line input accepts any analog component.
Why is there a built-in Moving Magnet phono stage?
The L/R X includes a Moving Magnet phono input so you can connect a turntable directly without a separate phono preamplifier. A phono stage does two essential jobs. It provides the large amount of gain a low-output cartridge needs, and it applies the RIAA equalization curve that reverses the frequency shaping baked into every vinyl record during mastering. Building this in means a Moving Magnet cartridge connects straight to the speaker, and the signal is amplified and equalized before entering the active chain. This is a deliberate nod to the vinyl-owning enthusiast, folding another traditionally separate box into the system.
What outputs does the L/R X provide?
The L/R X offers a subwoofer output and an inter-speaker link that can run either wired over USB-C or wirelessly via WiSA. The subwoofer output lets you add a powered sub for material that demands output below the speaker's own reach or for larger rooms, with the speakers handling the crossover handoff. The inter-speaker link is the more interesting feature, because it carries the audio between the left and right cabinets. WiSA is a wireless standard designed specifically for high-resolution, low-latency, tightly synchronized audio between speakers, so the wireless option is not a compromised Bluetooth-style link. If you prefer absolute reliability, the wired USB-C connection between speakers guarantees a locked, jitter-free signal path.
Why is there no coaxial digital input?
The L/R X deliberately omits a coaxial S/PDIF input while providing optical TOSLINK and HDMI eARC for digital sources. This is a considered choice rather than an oversight. With HDMI eARC handling television and high bandwidth digital audio, and optical covering older digital gear, the coaxial input becomes largely redundant for the modern use cases this speaker targets. Enthusiasts with a coaxial-only source will need to plan around this, but the remaining digital inputs cover the overwhelming majority of real-world connections.
Build, Materials, and Placement
How is the L/R X built and finished?
Each speaker weighs about 10.4 kg and measures 200 x 330 x 260 mm, and the pair is offered in Black, White, Blue, Green, Orange, and Real Walnut. That weight in such a compact footprint indicates substantial cabinet construction and internal bracing, which is exactly what you want for controlling resonance and giving the drivers a stable, inert platform to work against. A heavier, well-damped enclosure stores and releases less unwanted energy, keeping the sound clean. The Real Walnut finish signals the flagship intent, while the range of solid colors reflects that these speakers are meant to be seen and integrated into a living space rather than hidden.
How does the force-cancelling side firing affect placement?
Because the passive radiators fire from the sides and are force-cancelling, the L/R X is more forgiving of placement than a rear-ported design, though the radiators still benefit from some breathing room. The force cancellation reduces the vibration coupled into shelves or stands, so you get less of the boom and one-note bass that plagues small ported speakers pushed against a wall. You still want to give the sides a little clearance and observe normal stereo triangle principles for imaging, but the design tolerates real rooms well.
Where the L/R X Sits in the Lineup
How does the L/R X fit within the Cambridge Audio range?
The L/R X is positioned as the flagship active streaming speaker in the Cambridge Audio catalog, distinct from the brand's separates such as the Edge and CX component families. Where those lines ask you to assemble a system from a streamer, an amplifier, and passive speakers, the L/R X collapses that entire chain into two cabinets running the mature StreamMagic Gen 4 platform. It represents the fullest expression of Cambridge Audio's all-in-one thinking, aimed at the listener who wants genuine hi-res performance, comprehensive connectivity, and the tuning advantages of active design without managing a rack of boxes. For the experienced enthusiast, it is a considered argument that an integrated active approach can deliver serious sound with far less complexity.
