REL 212/SX Subwoofer


REL 212/SX Subwoofer

Short Description
212/SX builds on the strengths of the legendary 212/SE.
Product Finish
- Optional

212/SX builds on the strengths of the legendary 212/SE. Upgraded alloy drivers with carbon fiber blades are stronger, a new flat passive radiator extends even deeper and REL's PerfectFilter™ delivers crushing low bass with greater speed and air, taking 212/SX well beyond its illustrious predecessor.

quality meets quantity

At REL, a deeper understanding of quality underpins everything they do. So, whilst 212/SX thunders and shakes foundations, it also resolves detail and restores midrange warmth to its correct balance. At 1,000 watts with (4) 12” (350mm) drivers, 212/SX drives rooms hard and in multiple modes which allows it to create richer bass everywhere in a room.

REL 212/SX Subwoofer on the floor of a wooden floor space

Refinements to both REL's legendary ultra-fast filters and newly developed drivers produces harder slam and brings to life quieter, gentler moments, improving system performance at both extremes. Plays brilliantly with both high end 2-channel and large power theatre applications.

twin continuous cast™ alloy bass engines

Lightweight carbon fiber blades firmly attached to the rear of each active alloy cone serves to both strengthen the cone and quiet it. The twin 12” (350mm) active drivers now offer an additional 12mm of stroke and also benefit from updated suspension geometry and greater power handling. And a brand-new double-spider, high powered passive unit on the bottom delivers floor rippling low bass. The result is a major step forward in the 212 design, an already brilliant performer now playing louder with greater ease whilst better preserving the tiniest details of air and space with even greater precision.

dual continuous cast allow passive radiator

REL's uniquely tuned passive radiators use special suspensions, now with an additional 30mm of linear travel, to produce performance far beyond conventional subwoofers. Their new SuperProgressive™ passive radiator produces extremely long travel allowing for very loud output while retaining the variable stiffness of its suspension.

The down firing passive produces deep, floor-crawling bass that makes a room shudder. Mounted above the amplifier panel on the rear is the second passive. This unit produces wrap around “atmospheric” bass that adds air and shimmer to the sound. Coupling with either the rear wall or the rear corner of a room allows for bass to develop exceedingly long wavefronts and adds an ease and effortless quality unique to single-box designs.

whoever said "power corrupts" never heard a 212/SX

With incredible reliability in units now numbering in the thousands, the Gen 5 amplifier is a paragon of extreme power and reliability. At 1,000 watts of output, plus the ability to connect both High Level and .1/LFE simultaneously with optional state of the art wireless, 212/SX delivers the goods at scale. It does so with incredible grip and control in the extreme deep bass where most amplifiers get loose and lose control.

212/SX has an almost limitless sense of power, coupled with precision. Where others offer brute strength, REL deliver massive power and every secondary category of performance with ease and effortless versatility. Deafening output in a concert video or blockbuster movie? Check. Beautifully rendered female vocals accurately placed within a stone abbey? Check.

airship zero-compression wireless

REL seized the opportunity to develop a new high resolution, audiophile-grade uncompressed wireless system for 212/SX and their newer offerings in the Reference range. Airship™ is a new 5.8 gHz military-based wireless system built into a monolithic LSI chip that delivers incredibly fast bass. REL ship full bandwidth, not just bass, through this system that includes (2) channels. The first channel handles High Level Input and can be used for both stereo bass or use of a single channel with monoblock amplifiers. Simultaneously, Airship will process the .1/LFE channel necessary for special effects in film so both RCA and XLR inputs are provided. In the future, REL anticipate adoption of more active wireless loudspeakers reaching the market, so they included stereo low level inputs. With Airship, you’re ready for the future.

  • Type: (2) Front-firing active drivers, (1) rear passive, (1) down-firing passive
  • active driver size & material: (2) 12 in., 300mm long-throw, Continuous CastAlloy™ cone structure, cast chassis
  • passive radiator size & material: (2) 12 in., 300mm Carbon/Carbon flat cone structure, steel chassis
  • low frequency extension: -6dB at 18 Hz
  • input connectors: High Level Neutrik Speakon, Low Level stereo RCA, LFE XLR and LFE RCA
  • output connectors: High Level Neutrik Speakon, LFE RCA, LFE XLR
  • power output: 1,000 watts (RMS)
  • amplifier type: NextGen5 Class D
  • wireless capability: Yes- REL AirShip system [required]. Sold separately.

Protection System

  • fully electronic set safe
  • D.C. fault
  • output short
  • mains input voltage: 220-240 volts, 1120-120 volts for certain markets
  • fuses: 7 Amp semi delay 220 volts operation, 15 Amp semi delay 120 volts operation


  • width 14 1/4in, height 33in, depth 20 1/4 in
  • width 362mm, height 838mm, depth 514.5mm
  • net weight: 128 lbs. (58 kg)
  • finish: Piano Black Lacquer

Supplied Accessories

  • mains lead
  • neutrik speakon (10 metres nominal)
  • user manual

Overall Rating