What is the REL T/7i?
This means that the T/7i is designed and equipped slightly differently to many rivals at the price – as we shall cover – but not to the extent that REL feels that the T/7i can’t ‘cut it’ as a normal subwoofer to be used in an AV system. Nonetheless, the design leanings of REL are clearly visible in the T/7i and there is no shortage of burly looking rivals vying for your attention from various rivals so does it work?
To throw another variable into the mix, while the REL is designed with a view to a certain level of purism, it also has a rather unexpected convenience feature. If you are wondering about where best to place such a device and concerned that this doesn’t match with where you can physically run a signal cable, REL has a solution. More intriguingly still, REL says this solution doesn’t have any effect on the design ethos of the T/7i itself. There’s a lot to unpick here so we’ll crack on and see how the T/7i stacks up.
In principle this makes a fair degree of sense. While a forward firing driver places some restrictions in placement terms over a downward firing one, it alleviates many of the issues of using such a device on a suspended floor – the energy from the passive radiator being somewhat lower than the driver – and, in many parts of the world, this is rather more useful than any slight loss of positioning flexibility.
The material that the drivers have been made from have also been changed. They are still in essence made from paper but REL has delved into the business of paper composition and worked to create a driver that has less mass to it. This feeds into REL’s ongoing concern with the ‘speed’ with which the driver operates. Reducing the mass of the driver, reduces the amount of force required to start and in turn stop it. The driver can be moved more precisely and under a greater degree of control than would be the case if it was heavier and more inert. To give the driver a rigidity greater than that of a soggy paper plate, REL has then fitted a very large aluminium centre cap to the active driver. This acts as a stiffening component which doesn’t add much in the way of mass to the product.
The cabinet these drivers are placed in has been thickened and strengthened. It is now made from inch thick sections of MDF and feels extremely solid to the touch. The feet are integral to the cabinet and are capped with a plastic screw fitting that seems to avoid them marking surfaces that they are placed on. Compared to some of the burlier American designs we have looked at in recent months, the T/7i feels less monolithic – it can be lifted without the nagging feeling that a hernia is only seconds away – but it still manages to come across as solid and inert.
This amp will work with both a dedicated LFE input and a high level connection that is the REL trademark. This is intended to take the feed from an amplifier's speaker terminals and – crucially – because there is no high pass filter on this connection, it will impart some of the character of your amp to your sub bass. REL states in the manual that even if the LFE connection is in use, the high level connection should still be connected for optimal performance. While this is a contentious area, even if I did go about doing this I would have to switch my front speakers to large, which isn’t how my equipment is set up. It does – even if we leave subjectivity to one side for a minute – allow for the connection of the REL to a stereo amp with no preout. REL supplies a cable for this purpose and a conversation with REL HQ suggests that specialist ones are also available.
The T/7i can also be supplied – as seen here – with the Arrow wireless module. This is a proprietary system developed by/for REL that consists of a USB powered sending unit and a self-powered receiver that attaches straight to an RS-232 connection on the rear panel of the T7i. REL says the system is lossless and has a maximum range of 13.7 meters. Pairing it is simple enough and once done, provided the T/7i has power running to it, it can be placed anywhere. Interestingly the receiver module has both LFE and high level connectors in a mirror of the input board. REL states that the benefits of the high level connection as laid out by them will still be experienced via wireless.
How was the T/7i tested?
Sound Quality – Multichannel
Of course, when it is movie night, the performance of the T/7i is good with some small caveats. Firstly, if you absolutely must feel the full brunt of any impact and explosion in your lower intestine, this is probably not the device for you. REL quotes a lower figure of 30Hz and this can be comfortably exceeded in room but this isn’t a truly seismic device. There are some rather better bits of news though. The detail retrieval of the REL is extremely good. The various effects that make up the movement of tanks in Fury is delivered with real texture and an appreciable sense of the engine, tracks etc. This is bass as a fully developed aspect of the soundtrack and not a simple noise engine.
The truly outstanding quality of the REL comes to the fore when you put on something like the final live performance in Whiplash. This isn’t seismic bass, it can be handled almost in its entirety by a large floorstander, but with a 90Hz crossover a huge amount of the drumming is given over to the REL and it excels. In terms of sheer transient speed, the REL is able to match the Eclipse TD520SW – which is still the most accomplished subwoofer I have ever tested. REL’s obsession with driver weight and effective mass might seem curious but it really does pay dividends.
The Arrow wireless system is genuinely impressive though. Using one T/7i via a standard wired connection and one via Arrow shows no performance difference or latency issues. It has proved completely bulletproof in the time it has been installed and this has included interrupting the power and other issues. £200 for the system isn’t cheap (and it needs power of its own) but it does work exactly as specified making the T/7i an impressive bit of kit.
Sound Quality – Music
- Exceptional agility and transient speed
- Beautifully made
- Arrow module is well implemented
- Rivals at similar price can offer greater extension
- No continuously variable phase
- Fairly pricey with Arrow specified
REL T/7i Subwoofer and Arrow Wireless Module Review
Some time with a pair of them does reveal some singular abilities though. If you run a sub all the time and with speakers that need a 50Hz and up crossover in particular, the REL is effortlessly integrated, controlled and detailed. It has an agility and nuance that most rivals struggle to get anywhere near and for music especially, it sits in a very select field indeed. The inclusion of the Arrow wireless system further improves the basic flexibility and makes this a very capable subwoofer indeed. If you can run two, their ability to create a rich and believable low end is very compelling. It’s a premium solution but the REL warrants recommendation due to the depth of talent it displays.
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