REL S/850 Powered Subwoofer

REL's flagship single driver Serie S subwoofer combines reference inspired engineering, an 850 watt amplifier, and exceptional musical integration.

The New Flagship of the Serie S Family

The REL S/850 represents a significant evolution in the company's acclaimed Serie S lineup. Developed using lessons learned from REL's flagship Reference Series products, the S/850 was engineered to become the benchmark model within the modern Serie S family. Every aspect of its design has been refined, from the cabinet proportions and driver technology to the amplifier platform and Line Array capability.

The result is a subwoofer that delivers extraordinary power and extension while preserving the speed, articulation, and musical integration that have defined REL products for decades. Designed for both high performance stereo systems and premium home theaters, the S/850 provides a level of authority that allows it to anchor systems built around some of the finest loudspeakers available today.

Advanced CarbonAlloy Driver Technology

At the heart of the S/850 is a 12 inch CarbonAlloy active driver paired with a matching 12 inch long throw passive radiator. REL further enhanced the driver assembly with a lightweight pure carbon fiber center cap that replaces the heavier aluminum structures used in previous generations.

Reducing moving mass while increasing rigidity allows the driver to accelerate and stop more quickly. This translates into faster transient response, improved detail retrieval, and greater dynamic expression. Whether reproducing the attack of a kick drum, the resonance of a double bass, or the impact of cinematic effects, the S/850 delivers bass with exceptional control and realism.

850 Watts of Effortless Power

Powering the S/850 is REL's latest Linear Class D amplifier platform rated at 850 watts continuous output with peak capability approaching 1000 watts during demanding musical and cinematic passages.

REL's design combines the authority and slam traditionally associated with large Class AB amplifiers while maintaining the efficiency and control of modern Class D operation. The amplifier incorporates upgraded filtering components inspired by REL's flagship designs, helping deliver greater transparency, improved soundstage performance, and exceptional dynamic headroom.

Passive Radiator Design for Deep and Natural Bass

Rather than relying on a conventional bass reflex port, REL continues to employ a large down firing passive radiator system. The passive radiator features an advanced composite structure using carbon, fiberglass, and lightweight foam materials.

This design achieves deep bass extension to 19Hz while avoiding the turbulence, compression, and port noise often associated with traditional vented subwoofers. The result is bass reproduction that remains powerful and extended while preserving the speed and tonal accuracy required for serious music listening. The passive radiator is capable of more than 60mm of travel, allowing the S/850 to maintain composure during the most demanding low frequency passages.

Designed for Music First Performance

REL continues to distinguish itself through its commitment to musical integration. The S/850 incorporates the company's renowned High Level input system, allowing direct connection to the speaker outputs of an amplifier.

By receiving the same signal characteristics as the main loudspeakers, the S/850 blends naturally into the overall presentation. Rather than sounding like a separate bass source, it extends the capabilities of the loudspeakers themselves. Owners frequently report larger soundstages, greater harmonic richness, improved dimensionality, and more convincing musical realism after adding a properly configured REL subwoofer.

Equally Capable in Home Theater Applications

While music remains a central design goal, the S/850 is also an outstanding performer in home theater environments. Dedicated RCA and XLR LFE inputs allow seamless integration with surround processors and AV receivers.

REL uniquely supports simultaneous High Level and LFE operation. This means listeners can enjoy ideal integration for music playback while still experiencing the full impact and scale of modern movie soundtracks. The flexibility of this architecture makes the S/850 particularly attractive for systems serving both stereo and theater duties.

Built for Stereo Pairs and Line Arrays

One of the defining characteristics of the S/850 is its ability to grow with a system. A single unit provides exceptional performance, but REL specifically engineered the S/850 for stereo pair deployment and Line Array stacking.

Many experienced REL owners report that adding a second subwoofer improves room coverage, reduces nulls, enhances imaging, and creates a more enveloping presentation. The S/850 incorporates dedicated structural reinforcement and precision leveling features specifically designed to support advanced Line Array configurations. These systems can ultimately expand to three subwoofers per channel for truly extraordinary performance.

How the S/850 Compares to Carbon Special Black Label

The Carbon Special Black Label established itself as one of REL's most respected performance models. The S/850 builds upon that legacy with an updated CarbonAlloy driver platform, improved carbon fiber center cap technology, a redesigned cabinet, upgraded amplifier circuitry, enhanced passive radiator performance, and broader integration with modern REL Line Array systems.

For listeners seeking the most advanced single driver subwoofer currently available in the Serie S family, the S/850 represents the new reference point. REL specifically states that its performance exceeds even the former Carbon Special at the limits of dynamic capability while delivering greater refinement and transparency.

A Reference Grade Foundation for Serious Systems

The S/850 embodies REL's belief that a subwoofer should do far more than simply add bass. Through advanced driver engineering, powerful amplification, sophisticated integration methods, and extensive upgrade flexibility, it enhances every aspect of system performance.

Whether used as a single subwoofer, a stereo pair, or part of a full Line Array installation, the S/850 delivers the combination of speed, authority, scale, and musicality that has made REL one of the most respected names in low frequency reproduction.

Key Specifications Block

• Product: REL S/850
• Category: Powered Subwoofer
• Price: $3,999
• Active Driver:
  • 12 Inch Long Throw CarbonAlloy Driver
  • Front Firing
• Passive Radiator:
  • 12 Inch Carbon Carbon Flat Cone
  • Down Firing
• Amplifier Power:
  • 850 Watts RMS
• Peak Output Capability:
  • Approximately 1000 Watts
• Amplifier Type:
  • Linear Class D
• Low Frequency Extension:
  • 19Hz at 6dB
• Inputs:
  • High Level Neutrik Speakon
  • Dual RCA Low Level
  • RCA LFE
  • XLR LFE
• Outputs:
  • High Level Neutrik Speakon
  • RCA Low Level
  • RCA LFE
  • XLR LFE
• Wireless Compatibility:
  • REL AirShip Direct Optional
• Line Array Compatible:
  • Yes
• Finish Options:
  • Piano Black Lacquer
  • Gloss White Lacquer
• Width:
  • 19.25 Inches
  • 488 mm
• Height:
  • 16.125 Inches
  • 410 mm
• Depth:
  • 21.25 Inches
  • 540 mm
• Weight:
  • 93.5 Pounds
  • 42.5 kg
• Included Accessories:
  • AC Power Cord
  • 10 Meter Neutrik Speakon Cable
  • Line Array Hardware
  • Cloth Grille
  • User Manual
• Protection:
  • Fully Electronic Set Safe Protection
  • DC Fault Protection
  • Output Short Protection
• Recommended Room Size:
  • Medium to Large Rooms
  • Approximately 300 to 700 Square Feet
• Warranty:
  • REL Manufacturer Warranty

Why Buy From All Elite Audio

All Elite Audio is an authorized dealer for REL and every brand we carry. Every product we sell is sourced directly through authorized distribution channels and includes full manufacturer support.

Call: 443-402-5055

Text: 443-402-5064

Visit: 1921 York Rd, Timonium, MD 21093

FAQ

What makes the S/850 different from the previous Carbon Special Black Label?

The S/850 replaces the Carbon Special Black Label as the flagship single driver model in the Serie S family. It incorporates a redesigned CarbonAlloy driver platform, lightweight carbon fiber center cap technology, upgraded amplifier circuitry, and a new cabinet architecture. REL states that the S/850 exceeds the Carbon Special's performance at the limits of output capability while also delivering greater refinement and transparency. For many listeners, it represents the most advanced single driver subwoofer REL has produced in this category.

Is the S/850 designed primarily for music or home theater?

The S/850 was engineered to excel at both. REL's High Level connection system provides exceptional integration in two channel systems, preserving timing, tonal character, and musical coherence. Dedicated LFE inputs allow it to deliver the impact required for modern movie soundtracks. Many owners choose the S/850 specifically because it performs equally well in mixed use systems where both music and movies are important.

What is CarbonAlloy technology?

CarbonAlloy is REL's advanced driver platform designed to combine rigidity, low mass, and exceptional transient response. The driver utilizes lightweight materials and a carbon fiber center cap to reduce moving mass while improving structural stability. This allows the driver to start and stop more quickly, producing bass that sounds faster, tighter, and more detailed. The technology helps the S/850 maintain accuracy even during demanding low frequency passages.

Why does REL use a passive radiator instead of a port?

REL believes passive radiators offer several advantages compared to traditional bass reflex ports. They allow deep bass extension without introducing port turbulence, compression, or chuffing noise. The S/850's passive radiator is capable of more than 60mm of travel and was specifically engineered to handle the increased output of the new amplifier platform. This contributes to deeper, cleaner, and more controlled bass performance.

What size room is ideal for the S/850?

REL recommends the S/850 for medium to large rooms. The company specifically identifies spaces ranging from approximately 300 to 700 square feet as ideal applications. The powerful amplifier and large driver system allow the S/850 to energize substantial listening environments while maintaining excellent control and integration. Even in larger rooms, it retains the speed and refinement required for serious music listening.

Should I buy one S/850 or two?

A single S/850 delivers impressive performance and will satisfy many systems. However, REL has long advocated stereo subwoofer configurations because they improve room coverage, imaging, soundstage depth, and bass uniformity. Many experienced REL owners report that adding a second subwoofer provides a greater improvement than expected by reducing room related issues and creating a more immersive presentation.

What is a REL Line Array?

A REL Line Array involves stacking multiple subwoofers vertically per channel. The S/850 was specifically engineered to support this approach through dedicated structural reinforcement and leveling mechanisms. As additional subwoofers are added, output capability increases while bass becomes more effortless, spacious, and dynamic. REL considers Line Arrays among the highest performance bass systems available for reference audio installations.

Does the S/850 support wireless operation?

Yes. The S/850 is fully compatible with REL AirShip Direct wireless technology. This optional accessory allows flexible placement without the need for long signal cables running across the room. REL designed AirShip Direct to preserve the speed, transparency, and authority expected from the S/850 while maintaining installation flexibility.

How does the S/850 compare to the 212 Black Label?

The S/850 is REL's flagship single driver design within the Serie S range and emphasizes a balance of speed, refinement, and room friendly proportions. The 212 Black Label utilizes a four driver architecture and delivers greater overall radiating area and output capability. For many medium to large rooms, the S/850 offers more than enough performance while occupying a smaller footprint. The 212 Black Label becomes attractive when maximum scale and output are the primary goals.

Where can I buy the REL S/850?

You can purchase the REL S/850 directly from All Elite Audio. As an authorized REL dealer, we provide manufacturer supported products, expert system matching guidance, and personalized service before and after the sale. Call 443-402-5055, text 443-402-5064, or visit 1921 York Rd, Timonium, MD 21093.