REL HT/1205 MKII subwoofer

HT/1205 MKII (a.k.a The Cannon)

HT/1205 MKII establishes a new performance standard for affordable home theatre subwoofers. Avoiding electronic gimmickry in favour of properly balanced priorities; cabinets that are right-sized, solidly braced and beautifully finished. A sparkling new amp design that effortlessly delivers 500W into an all-new CarbonGlas™ 12” (300mm) driver. The sexy new black lacquer top plate has a subtle REL logo floating on top, while the expensively wrought black line-grained composite for the cabinet looks the business.

HT/1205 MKII plays 50% louder than its predecessor, while also delivering more precision and subtlety. It is capable of output levels more commonly found in models well over $1,000/£1,000. Fantastic for music and available HT-Air rounds out a perfect offering.

Key Features

• 500 Watt Class D Amplifier
• 12" Carbonglas driver
• Optional HT-Air™ Wireless transmitter
• Dual-purpose Low-Level stereo RCA or LFE RCA
• At 6 dB louder than any previous REL within 50% of its price

Performance home theatre

Serie HT is designed specifically to answer the challenge of creating affordably priced, exceptionally dynamic, pure home theatre-powered subwoofers. The HT/1205 MKII is the ideal combination of a lightweight, modern 12” CarbonGlas™ (300mm) driver coupled to a powerful 500W Class D amplifier that runs cool, producing extraordinary dynamics. Internally, we developed specially adapted home theatre input filters that produce extremely flat bass down in the 20s.


We set out to build the loudest, relatively compact 12” unit available for pure home theater use, and at truly attractive pricing. You’ll be the judge of how well we accomplished that goal, but critics are already lining up for reviews. We believe the HT/1205 MKII is destined to become a modern classic with svelte cabinet dimensions finished in an attractive, yet purposeful line-grained black aluminium look and topped by a 12mm thick beautifully polished top that serves to damp vibrations on the critical top surface of the cabinet.


For REL owners already enjoying our Reference, Serie S and T/i subwoofers designed for both 2-channel and theatre use, the HT/1205 MKII is designed to supplement their system’s .1/LFE output to produce extremely high output for chest rumbling home theatre special effects.

The beautiful new cabinetry is bespoke; it has new textures, proportions, and finishing touches previously unseen in the category. Lower, sleeker cabinetry borrows proportions drawn from our new Reference models. Over the years, our experiments have established that this results in a faster, deeper presentation of bass—all while looking smashing. Your eye is immediately drawn to the top panel, whose entire surface is finished in 5 coats of hand-polished piano black lacquer. A discreet REL logo floats within the top layer of lacquer whilst the body of the cabinet is clad in horizontally streaked, line-grained composite. The entire affair looks expensive, bespoke, and tastefully restrained. Additionally, you can stylishly combine it with either Serie T/x or Serie S in large, fully immersive REL HT/3D™ setups.*

The HT/1205 MKII’s driver is a 12” (350mm) CarbonGlas™ construct as it has always been, but all its components were beefed up. It is improved in both large and small ways, enabling it to deliver the greatest performance possible. Lightweight, stiff, and quiet, the combination of glass fibre primary cones with true carbon fibre centre caps results in a cost-effective yet pistonic cone. Larger, more powerful magnets produce more energy. Upgraded suspension designs control the HT/1205 MKII’s output all the way out to the limits of both the amplifier and the driver. The result is crazy output, while the HT/1205 MKII remains fast and liquid.

Amplifiers do the heavy lifting in a theatre subwoofer. We turned to a true tier-one amp supplier to build our latest design for us—they did not disappoint. They included thicker boards, upgraded the power supplies, and did all the stuff that resulted in a brutally powerful amp with remarkable longevity. Additionally, the MOSFET power modules rated at 800 watts mean this amp is just cruising at its 500-watt rating. It produces truly awe-inspiring sound. While the theatre gets all the headlines, the HT/1205 MKII’s big secret is that it sounds sublime in musical applications. Big and robust-sounding, it is sure to become an instant classic.

PerfectFilters™: Where it All Starts – Amplifier

REL input filters are renowned throughout the audio world. They bring together ultra-fast crossovers, elevation filters that extend the flatness of deep bass, and explosive-sounding integrated limiters. This compact series of analogue circuits is REL’s secret recipe in both music and film sound. Refined in this second generation, the secondary filters are much higher in frequency; they make the rarefaction of air in the sound of an explosion feel that much more realistic. Also, our latest circuit includes an all-analogue subsonic filter that begins as low as 8 Hz to minimize the effects of infra-noise from soundtracks that extends well below the resonance point of the driver. The result is incredible delivered power with the ability to play all the way to the driver’s limit without distortion.

Wired for sound used to entail long runs of cable strewn across the floor. With our optional HT-Air™, great sound has become “un-wired.” Wire has been replaced by a tiny transmitter and matching receiver that sends an incredibly fast 5.8Ghz wireless signal up to 60 feet with no digital compression. This affordable circuit includes the same LSIC chip that powers our state-of-the-art AirShip II, minus the expensive analogue-to-digital and digital-to-analogue (DAC) converters. The HT-Air is perfect for the .1/LFE signals using RCA connectors that are HT/1205 MKII’s primary mission.

At 6 dB louder than any previous REL within 50% of its price.

Who is REL?

REL subwoofers are engineered to deliver deep, powerful bass in both stereo and multi-channel systems. Even full-range loudspeakers can often not extend to the lowest bass frequencies, which reduces the impact and involvement for the listener in both music and movie playback.