The special edition REL Acoustics T/9x SE subwoofer in Italian red may be a little too racy for some hifi fans, but I love the vibe this strikingly colourful sub-bass speaker brings to my listening room. It’s more than a flashy supercar paint job to one of REL’s most popular mid-series models, though. This limited edition version of the Serie T/x flagship sports an upgraded centre cap to the forward-firing ‘attack’ driver and a re-tuned chassis suspension for faster low frequency handling and scale.
Bridgend-based REL Acoustics has done more than most to champion the benefits of active sub-bass systems, as potential solutions to underperforming music setups. We’ve reviewed several of its designs over the years, including the top class £2,499 S/510 that impressed us in 2023 to the £899 HT/1205 mkII in 2022, and the great value T/5x at £699 in 2021. Without exception, I’ve been impressed by the bass benefits each has brought to my music setup.
Looking resplendent in supercar Italian red, the limited edition T/9x SE is also available in Le Mon (yellow), and Tangerine Dream (orange)
Loud and proud
As a limited edition version of the continuing REL Acoustics T/x series flagship, the SE’s enhancements boost the price to £1,549 – compared to £1,399 for the standard model (available in black or white high-gloss finishes). That’s just £150 more for upgrades that boost the sub’s attack and output efficiency. Now that doesn’t seem unreasonable for the performance step up and the sexy limited edition colour options on offer, and demonstrates the audio specialist’s commitment and passion to masterful acoustic solutions without breaking the bank.
The SE version is available in a trio of new high-gloss finishes, including Italian red (as reviewed), Le Mon (yellow), and Tangerine Dream (orange). As with all the Serie T/x models, cabinet construction on the SE is exquisite and maintains REL’s meticulous high-gloss finish that applies multiple paint layers both horizontally and vertically. While the new eye-catching colour options are something to shout about, it’s the SE’s acoustic upgrades that the company is most proud of, and will impress low-frequency fanatics the most.
The T/9x SE’s 10in (250mm) downward-firing driver with alloy centre cone and a large rolled surround is actually a passive bass radiator to help provide extra energy
Massive attack
With a 10in (250mm) long-throw, forward-firing driver similar to the T/9x, the SE edition swaps the alloy dust cap for a carbon fibre version to dig deeper and hit harder. According to REL’s chief designer, John Hunter, upgrading to the carbon fibre material has made the 10in driver lighter and stiffer for better bass attack performance that’s more efficient with the built-in Class AB power amplifier rated at 300W.
Aside from the vibrant colour options, cosmetic differences run to the SE’s main driver that’s missing the REL Acoustics name and crown logo due to the textured nature of the new carbon fibre centre cap material. The REL branding on the chrome-plated feet has also been swapped to the crown insignia in soft grey, and there’s a new carbon fibre bezel surrounding the large alloy top-plate. Internally, the T/9x SE’s sealed cabinet uses the same robust cabinet bracing as the original, and the dimensions and weight measure the same.
I should point out that while the four chrome-plated feet on the T/x series provide good surface area contact with the floor and strong stability, the cabinet can’t be stacked on top of another for line array configurations. Also, the T/x series doesn’t have carry handles like the step up Serie S models, so it’s important to take care and maintain a firm grip on the cabinet when unboxing and manoeuvring its 20.6kg heft into position.
The T/9x rear panel is clearly laid out with RCA and Speakon connectors, plus Hi/Low Level and LFE .1 Level trim and crossover controls
Room service
REL’s sub-bass systems are fit and forget designs, and there are practical user guides and videos to help with the installation process, as well as a helpful Subwoofer Finder tool to find the right model for your speakers and price point.
I know from previous trials with speaker placements in my room where a subwoofer works best, and the T/9x SE was sited to the right of the stereo left speaker, firing down the room towards my usual listening position. Integration controls provide high and low-level input adjustment as well as LFE (low-frequency effects), variable crossover control and standby mode. There’s also a reversible phase switch.
For this review, I connected the T/9x via the high-level input using the supplied 10m (33 feet) cable terminated with a Neutrik Speakon lockable connector at one end, and bare wires at the other, connected to the speaker outputs on my amplifier.
For users who want to connect wirelessly, the T/x series is compatible with the company’s Arrow Wireless (£220) add on. It uses a high-quality, zero-compression audio signal from the sending device to the receiver, and although not supplied for this review, it has proved to be reliable and stable with superb sound in my previous tests.
As with other REL subs, there’s no smart app to integrate the T/9x SE into my system from the comfort of the sofa. While that isn’t a major concern, I found it handy to have someone else around to adjust the controls at the back of the REL while I listened for the optimum sub-bass integration with the main speakers from my regular listening position on the sofa.
Inside the T/9x SE, the built-in high-current Class AB amplifier rated at 300W power output is even more efficient at energising the long-throw forward-firing 10in (250mm) driver owing to the lighter and stiffer carbon fibre centre cap
Performance
As hifi lovers will know, listening room acoustics have a major influence on a system’s performance. While I love the sound I get with the majority of speaker setups in my listening room, it can be a challenging environment to get the low frequencies sounding balanced. I live in a 16th Century cottage and the unconventional room shape and size (it was originally two separate rooms now knocked into one) means I have the speakers arranged a little wider than the suggested hifi convention, and my listening position is quite far back. There’s some toe-in applied to the main speakers to compensate for the arrangement, but despite my floorstanding speakers being capable of digging deeper than most, the lower bass lacks the output energy I enjoy when sat at the listening position. Thank heavens, then, for REL’s sub-bass speaker systems.
In the past, I’ve found a carefully integrated sub a great solution. In fact, I’ve been living with REL’s top class S/510 alongside a pair of Dynaudio Excite X38 floorstanders and Musical Fidelity M6 500i integrated amp for a while now. The combination delivers just the right level of energy without overpowering other parts of the room, and makes my system sing.
The T/9x SE has the same-sized active driver as the S/510 but a smaller down-firing passive driver for what REL calls “floor crawl bass energy”. Despite this, the T/9x has a similar level of attack energy I’ve come to expect from my regular sub when playing bass-heavy tracks.
I’m streaming via the recently reviewed Volumio Rivo connected to the even more recently reviewed iFi Audio iDSD Diablo 2 DAC, and Newton Faulkner’s version of Massive Attack’s Teardrop (16-bit/44.1kHz FLAC via Tidal) is one of my playlist‘s go-to tracks. The system’s sound with the T/9x SE in place has all the depth I’ve come to expect, and the track’s ultra deep bass notes are clear and more audible in my room without over driving it. There’s more clarity around the main drums, too, and I’m convinced these sound richer and more natural with the T/9x SE in place.
Listening to a selection of acoustic folk tracks, including The Ballad of the Runaway Horse by Jennifer Warnes and Easy Money by Rickie Lee Jones (both streamed at 16-bit/44.1kHz FLAC via Tidal), and the double bass sound that underpins both songs shines through, highlighting the sense of scale and richness these recordings have. Similarly, with Prokofiev’s Troika Song performed by the Los Angeles Philharmonic Orchestra, conducted by André Previn (one of the classical tracks on our Alternative Xmas Anthems playlist), the lowest notes of the performance are delivered with tremendous power and more bass weight than I remembered.
The T/9x SE’s lighter attack driver material means that the sub-bass system’s timing always feels fast and accurate, and seamlessly integrated with the main speakers. There’s no sense of sluggishness or overhang when playing tracks from The Pet Shop Boys’ album Nonetheless on vinyl. The lush orchestration mixed with the toe-tapping disco beats sounds awesome with the sub in situ, and the extra clout it delivered meant that every song I played on my Technics SL1200G turntable connected to a Chord Electronics Huei MM/MC phono stage was bursting with life.
In Summary
The courageous colour choice may not be for everyone. But in a sector that’s traditionally offered sub-bass systems in black or wood finishes, the limited edition REL Acoustics T/9x SE is shaking up the market in more ways than one.
Connectivity options aren’t quite as wide as systems further up the company’s range, and if you already own an original T/9x then the SE version may not be a major upgrade. On the other hand, for first time buyers looking for a mid-sized, sub-bass speaker system that looks as hot as it sounds, the REL Acoustics T/9x SE builds on the popular flagship, and is a top recommendation at the price. Grab it while it’s hot!
