REL S/850 Subwoofer – Reference-Level Power and Musical Precision

Effortless Power Tuned for Musical Authority

The REL S/850 subwoofer is designed for listeners who demand uncompromising bass performance combined with refined musicality. Inspired by innovations from REL’s Reference Series, the S/850 combines an 850-watt Linear Class D amplifier with advanced CarbonAlloy™ driver technology to produce explosive dynamics, exceptional clarity, and effortless scale.

Whether integrated into a high-end stereo music system or a premium home theatre setup, the S/850 delivers powerful, controlled bass that fills medium to large listening rooms with authority and precision.

Key Features

• 850-Watt Linear Class D Amplifier for fast, controlled power delivery

• 12-inch CarbonAlloy™ active driver paired with a 12-inch long-stroke passive radiator

• Designed for music and home theatre systems in medium-to-large rooms

• Ideal for stereo pairs and REL Line Array configurations

• Optional Premium Wood Grille, crafted from natural materials with unique grain patterns

Stunning Design Meets Raw Performance

The S/850 represents the pinnacle of the REL Serie S subwoofer range, with its engineering innovations influencing the entire product line. Every element has been refined to push performance further than ever before.

The result is a subwoofer capable of incredible transient attack, immense output, and extraordinary dynamic range—surpassing even the legendary Carbon Special at the limits of performance.

Lightning-fast transients, deep effortless bass, and exceptional tonal richness combine to deliver remarkable nuance that enhances both music listening and cinematic experiences.

Precision Cabinet Design

The S/850 cabinet features refined proportions—longer, lower, wider, and deeper—giving it both visual presence and acoustic advantage.

Thoughtful design details elevate its aesthetic and functionality:

• Clean precision creases that reflect light elegantly

• Warm silver-gold badges inspired by raw titanium finishes

• Stainless-steel handles recessed within sculpted elliptical cut-outs

• Precision-milled billet cylinders beneath each front rail for accurate levelling

Inside the cabinet, thick aluminium plates secure the handles and provide structural reinforcement for safe stacking when used in REL Line Array systems.

For added character, the S/850 can be paired with an optional Premium Wood Grille, bringing natural warmth and individuality to modern interiors.

CarbonAlloy™ Driver Technology

At the heart of the REL S/850 lies an advanced 12-inch CarbonAlloy™ active driver, designed through thousands of hours of engineering refinement and critical listening.

Key innovations include:

• Lightweight pure carbon-fibre centre caps

• Reduced moving mass for faster response

• Increased cone stiffness for improved control

These upgrades allow the S/850 to deliver explosive dynamics while preserving delicate detail. The driver can reproduce the quietest passages with subtle nuance while maintaining immense power for demanding low-frequency effects.

This balance of speed, precision, and authority is a defining hallmark of REL subwoofer design.

High-Performance Passive Radiator

Complementing the active driver is a newly engineered down-firing passive radiator designed specifically for the S/850’s powerful amplifier and extended driver excursion.

The radiator’s flat piston surface is constructed from an advanced composite of:

• Carbon fibre

• Glass fibre

• Closed-cell structural foam

This design makes the radiator 40% stiffer and significantly lighter than previous versions.

With over 60 mm (2.4 inches) of travel in each direction, the passive radiator dramatically enhances:

• Low-frequency extension

• Dynamic impact

• Bass authority

Together, the active driver and passive radiator create a subwoofer capable of delivering deep, room-filling bass with exceptional control and speed.

REL Serie S Line Array System

REL’s Serie S Line Array configuration allows the S/850 to scale performance dramatically. Starting with a stereo pair, systems can expand to three subwoofers per channel, creating an immersive floor-to-ceiling soundstage.

This configuration delivers:

• Greater bass consistency across the room

• Increased dynamic headroom

• Expansive soundstage height and depth

The S/850 introduces a precision-milled knurled aluminium adjustment knob integrated into the body rails. This feature allows the bottom unit in a Line Array stack to be perfectly levelled on uneven flooring such as thick carpets or padded surfaces, ensuring stability and optimal acoustic performance.

Airship Direct™ Wireless Connectivity

In high-performance audio systems, cable management can sometimes limit placement options. REL solves this with Airship Direct™, an optional wireless transmission system designed for uncompromised audio performance.

Airship Direct™ transmits wide-bandwidth compound signals, simultaneously carrying:

• High Level signals

• .1/LFE home theatre signals

Even with the immense power and output of the S/850, Airship Direct™ maintains REL’s signature speed, transparency, and bass authority.

The compact wireless module connects directly to the rear panel and remains discreetly hidden, allowing seamless switching between music listening and cinematic playback without adjusting controls.