Carbon Limited


Carbon Ltd. Is a special offering that provides a unique blend of our Reference carbon fibre 12” driver and our finest passive driver from the 212/SE, all packed into the proven S/5 chassis, which is then fitted with triple chrome plated hardware. The result is stunning, for the eyes and the ears.

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Due to a Covid-19 exposure in our third party warehouse we are experiencing 5 day shipping delays. Additionally, orders placed from November 25th to November 30th will be processed when our office reopens on December 1st after the Thanksgiving holiday. Due to high order volume over the Thanksgiving weekend this may cause a 1-3 day delay in addition to warehouse processing and freight transit time. Note, regarding shipping times: our carriers are unable to guarantee delivery due to Covid-19, quoted delivery times may potentially be impacted.

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SKU: 857316005362 Category:

Carbon Limited

Reference Sound, Smaller Size

We wondered what might be accomplished if we shoehorned our Reference driver into a standard cabinet. Might we be able to deliver something special for systems where space was at a premium? To keep up with it, we would need our highest output passive driver and plenty of power to drive it all.

We began with our finest 12” driver, the ultra-longstroke G-1MKII carbon fibre driver, noted for its speed and purity. To keep up with its dynamics, we fitted the light alloy passive from our 212/SE driven by the 550 watt amplifier from the S/5 SHO, here with a few more jewels of output. The heavyweight 30mm-thick cabinet, borrowed from the hugely successful S/5, is our most advanced standard cabinet, with hardwood bracing employed extensively throughout its interior to quiet unwanted vibration. Turning to the visual presentation, true triple chrome-plated hardware was used for the exclusive top badge and matching feet which reflect their surroundings, while polished stainless T-304 steel handles complete the ensemble. Carbon Ltd. embodies all of our modern capabilities in a single, compact form.

In the end, we have achieved something special, but only available in limited quantities because many of the processes needed to build Carbon Ltd. do not lend themselves to large scale production.


Modern & Artisanal Craftsmanship

Lacquer, Carbon, Chrome & Enamel

The badge requires three months to produce a single run, we use 9 separate processes just to produce the perfect triple chrome plated finish. The feet appear almost liquid, reflecting both their surroundings and the owner’s taste exquisitely. Chrome plating over Old World die-stamped embossed logos, carefully back-filled using organic enamel; another age-old technique that harkens back to a time of carriages and horses. Carbon Ltd. blends modern and antique artisanal craftsmanship into a single, seductive whole.


Sound Beyond Its Size

Inspired by the G/1 mk II

A perfect 12” carbon fibre driver is a thing of genuine beauty, both physically and technically. Carbon fibre offers the ideal combination of ultra-light weight–a REL touchstone for over a decade–with a tough, resilient and extremely quiet cone structure that produces wickedly fast, sensationally deep low bass. To produce the high output levels our clients expect, we endowed this bass engine with a full 4” (100mm) of stroke, enough to supply the prodigious output appropriate for such a special model.


Fast, Extended Lows

NextGen2 550W Digital Amplifier

REL amplifiers are expected to produce very fast, tightly controlled deep bass with explosive dynamics, and do so for years on end. The 550W NextGen2 amplifier offers standard setting reliability with many thousands of this high current amplifier having been produced over the past decade. And with industry-leading fast, musical input filters, transients so important to the full enjoyment of music and theatre arrive without dynamic compression or the sort of dull, heavy character many subwoofers are guilty of delivering.



Longbow™ Wireless Connectivity

Carbon Ltd. includes a state-of-the-art wireless Longbow receiver built into the filter board, seamlessly integrating modern wireless into a classic subwoofer design. All you need to do is purchase the Longbow Wireless transmitter. Zero compression means that musical and theatrical signals are beamed one-to-one, in a bit perfect manner without resorting to severe compression best suited to mobile telephones. Discrete D/A convertors and A/D encoders are used internally, along with separate analog and digital power supplies. It even comes out of standby flawlessly, as the main on-off standby circuit takes into account Longbow’s wireless signal and comes to life as intended.

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Carbon Limited

Suggested Retail: $3,499

Carbon Ltd. Is a special offering that provides a unique blend of our Reference carbon fibre 12” driver and our finest passive driver from the 212/SE, all packed into the proven S/5 chassis, which is then fitted with triple chrome plated hardware. The result is stunning, for the eyes and the ears.



Closed box, front-firing active woofer

Active Driver Size & Material

12 in., 300mm long-throw, carbon fibre cone with inverted carbon fibre centre cap

Passive Radiator Size & Material

12 in., 300mm Continuous CastAlloy™ cone structure, cast chassis

Low Frequency Extention

-6 dB at 20Hz (in Room)

Input Connectors

High Level Neutrik Speakon, Low Level stereo RCA, LFE RCA, SMA for wireless antenna

Output Connectors


Power Output

550 watts (RMS)

Amplifier Type

NextGen2 Class D

Wireless Capability

Longbow (Optional), Zero Compression, Individual discrete D/A and A/D Encoders

Protection System

Fully Electronic Set Safe


D.C. Fault


Output Short


Mains Input Voltage

220-240 volts, 110-120 volts for certain markets


5 Amp 220 volts operation, 9 Amp 120 volts operation


W x H x D

17.5 x 18 x 20 in. (444.5 x 455.5 x 507 mm)

Net Weight

78.4 lbs. (35.6 kg)


Piano Black Lacquer, 8 coats

Supplied Accessories

Mains Lead


Neutrik Speakon

Yes (10 Meters Nominal)


Users Manual


In the interest of product development, REL Acoustics Limited reserve the right to vary these specifications without notice.