REL S/550 Subwoofer

Take in the design as a whole: horizontal strakes carved into the side walls, elegant elliptical returns that cradle handles finished in a warm golden-silver, echoing raw titanium. Everywhere you look, thoughtful details emerge—but the purpose is clear. This generation delivers the seemingly impossible: a larger cabinet that is lower, wider, and deeper, yet visually lighter.

The added internal volume gives drivers greater freedom and amplifiers improved efficiency, while updated internal bracing keeps cabinet resonances firmly under control. Subtler touches also make a difference—badges that disappear into the grille cloth, silver accents that rest quietly within the cabinet plane, and model numbers etched discreetly into the front rails, visible only when stacked in a Line Array.

An optional Premium Wood Grille adds warmth and individuality, while front-rail leveling adjusters ensure effortless setup, even on uneven floors. Together, these refinements reflect REL’s philosophy that great design is as much about thoughtful usability as it is about beauty and performance.

The new S/550 10” high-amplitude driver has been completely rebuilt—only the cast frame remains. Its CarbonAlloy™ cone, capped with pure carbon fiber, sharpens attack and smooths decay, letting notes fade naturally into silence. A redesigned suspension allows greater travel, easily handling the amplifier’s added power.

In listening, the driver feels supple and effortless, free from strain. Because it’s lighter, the amplifier works less, yet delivers more power, allowing the driver to move further and play louder than ever before. The result is nothing short of a revelation.

Rated at 550-watts, the Pure Class D amplifier outpaces its predecessor—but numbers tell only part of the story. In our lab, this unit delivers 600-watts continuous with no strain for extended periods of time. Its crest power is fully 50% more than its predecessor.

Premium polypropylene capacitors, like those used in our Reference models, enhance the input filters, resulting in a more open soundstage with greater transparency. As always, fed by our second-generation PerfectFilter™, the deep bass is utterly remarkable for a subwoofer whose footprint is so tidy.

REL uses 100% analogue input filters—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.

For systems where High Level isn’t possible, the low-level input uses the same analog filter circuit, available via both RCA and XLR connections. 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.

REL Line Arrays are celebrated for their sound staging and dynamics, admired across the high-end audio community. They’re designed to grow with the listener: start with a stereo pair, expand to four, and ultimately build a full six-unit stack for floor-to-ceiling authority. Precision mechanical couplers lock each upper unit securely to the anchor REL below.

The S/550 is the ideal entry into this world, delivering the speed, nuance, and scale that define Line Array performance. It offers a scalable foundation for music and home theater enthusiasts looking to experience the benefits of REL’s vertical bass architecture in medium-sized rooms.

Sometimes the best wire is no wire. 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 scale and output of S/550, 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™.

Key Features

• 10″ CarbonAlloy™ Active Driver with 12″ Down-Firing Passive Radiator
• 550-watt Pure Class D Amplifier (600W peak)
• Carbon fiber cone cap for speed, clarity, and control
• Fully analog input filters for high-speed, natural sound
• High Level, Low Level RCA & XLR, and LFE connections
• Compatible with Airship Direct™ wireless module
• PerfectFilter™ for deep, extended low-frequency response
• Front-rail leveling feet for easy placement
• Optional Premium Wood Grille available
• Ideal for music and home theater systems in medium-sized rooms
• Expandable via REL Line Array (up to six units)