Supporting this advanced active driver is a newly engineered down-firing passive radiator. Purpose-built to handle the extreme throw distances produced by the S/850’s more powerful amplifier and driver system. Its flat, primary-piston surface—crafted from carbon, glass fibre, and light, stiff closed-cell foam, represents an evolution of prior designs but is now 40% stiffer and significantly lighter. With over 2.4" (60mm) of travel in each direction, it expands dynamics and low-frequency authority, unlocking the full scale and impact of the S/850.
Driven to Perfection
The down-firing passive radiator in the new Carbon Special Black Label is an elevated component, hand-selected to meet the tightest tolerances within our design parameters. Each is chosen for its ability to deliver the most precise pistonic behavior, resulting in greater transparency and control than any prior generation.
At REL, development begins with the driver the foundation of sonic character. For the Carbon Special Black Label, we designed a 12" all-carbon fibre unit capable of handling three times the peak power of its predecessor. A newly engineered suspension allows the cone to travel over 60mm front to back, producing extraordinary dynamics with complete control.
The result is bass that is effortless, powerful, and fluid, extending lower with more authority than ever before. Whether capturing the subtle textures of live music or the impact of modern cinematic soundtracks, this latest-generation driver system redefines what’s possible across the medium-chassis class.
Amped Up
Carbon Special Black Label is powered by a 900-watt hybrid amplifier that combines the rich current delivery of Class A/B monoblocks with the efficiency of a Class D output stage. A 15-pound power transformer and extensive heatsinking form the foundation for high-current performance, adding to the model’s weight and commanding authority. This design sustains peaks of 1,250 watts with ease, delivering louder, cleaner, and more controlled bass than any previous medium-chassis REL. The result is an amplifier that unites raw power with the composure and finesse that define Black Label.
Analog Filtered to Perfection
We choose analog because it is the only way to achieve truly natural sound. All REL input filters are 100% analog—among the fastest ever offered in a subwoofer. At the core is our renowned High Level Input, which connects directly to the speaker outputs of your main amplifier. This doesn’t draw power; instead, it carries the full sonic signature of your system, allowing REL to blend seamlessly with your speakers—a quality reviewers have praised for decades.
For systems where High Level isn’t possible, our low-level input uses the same analog filter circuit, available via both RCA and XLR connections, to deliver the speed, naturalness, and integration REL is known for. And in theater or dual-use systems, REL uniquely allows High Level and .1/LFE to run together—so music benefits from natural integration, while movies deliver the full impact intended by the mix.
Serie S Line Array
REL’s Line Arrays are revered for producing sound staging and dynamics that rival the world’s finest systems. Designed to grow in pairs, a Line Array can begin with a simple stereo pair, expand with a second, and ultimately rise to three units per channel, delivering floor-to-ceiling authority and scale.
Carbon Special Black Label models now feature a precision-milled knurled aluminum adjustment knob integrated into the body rails. This knob allows the bottom subwoofer in a Line Array to achieve perfect level on uneven or soft flooring such as thick-pile carpets or dual-pad installations ensuring a safer, more stable foundation. Purpose-built exclusively for Line Array use, these adjustment knobs enable ideal setup and secure performance without compromise. (Note: 212 Black Label does not include these adjustment knobs.)
Carbon Special Black Label was engineered from the ground up to support the step-by-step build of a Line Array system. Each unit includes precision mechanical couplers that lock the upper and middle subwoofers to the anchor REL below, ensuring rigidity and optimal acoustic coupling. Proven at international shows and in private listening rooms, Carbon Special Black Label Line Arrays achieve true state-of-the-art performance even when paired with stand-mounted monitors or compact floor standers in medium-sized rooms.Imagine the presence and impact of a half-million-dollar system, brought to life in a modest space.
Wired For Sound…Wirelessly
Sometimes the best wire is no wire. Quality cables are a given in high-end audio systems, but there are occasions where it is impractical, unsafe, or unsightly to drape a cable across the room. REL delivers the ultimate solution with Airship Direct™, our optional wireless system that transmits wide-bandwidth, compound signals, carrying both High Level and .1/LFE simultaneously. Even with the immense scale and output of Carbon Special Black Label, Airship Direct™ preserves the speed, transparency, and authority that define REL. It allows seamless transitions between music and movies without ever touching the controls, all from a single module that plugs neatly into the rear panel and stays invisible in your room. Simple, direct, uncompromised: Airship Direct™.