On the one hand, this is a review of the REL T/9i subwoofer. On the other hand, this is a review of the REL T/9i subwoofer. Because this is a review of two REL T/9i subwoofers. More specifically, this is a survey of how most people get deep bass very wrong, and how a pair of well-integrated RELs are the exception.
Let’s start with the T/9i itself. The top dog in REL’s new core T/i series, the T/9i is a solid square piano gloss cube with a new front firing 254mm long-throw drive unit with a steel chassis and a large inverted dust cap. This is joined by a matching 254mm downward firing passive radiator. Adding depth to the cabinet makes the cabinets act like a concert hall, designed to properly dissipate rather than propagate the back wave.
Additional cabinet wall mass was needed to keep up with the new drivers and so these cabinets are now a full 25mm wall thickness, which accounts for the tremendous solidity one hears in the sound of a T/9i. The rear of the T/9i is taken up by a panel containing the 300 W amplifier with high and low-level inputs, a high-level output, and controls for volume and crossover point. Traditionally, home cinema users run a line level phono cable to the low/LFE input, while audiophiles run a high level input from the speaker terminals to a Neutrik Speakon connector. This cable is supplied, and is typically connected at the loudspeaker end using three flying wires that connect to both of the left and right positive loudspeaker terminals and one of the negative terminals. An uncompressed wireless ‘Arrow’ connection is also available at a premium. Ignoring Arrow, adding a second subwoofer means tying together the left and right positive flying leads, and using this connector more like a conventional loudspeaker cable. So the right subwoofer is connected to the right channel, and what’s left is left. You know what you’re getting with REL; a fast, taut, and deep bass that manages to keep up with the speed of your loudspeakers. Unlike most subs, REL goes after the precision and subtlety in bass, rather than quantity and level. This is what makes the brand so attractive to audiophiles; rather than simply adding more bass, these subs simply add an underpinning of bass reinforcement, allowing the loudspeakers to act more openly and engagingly in the upper registers. Paradoxically, a well set up REL may end up producing a sense of less bass, but the degree of control it offers over the bass entirely justifies its inclusion. The T/9i extends that authority and control over the bass, however it is also powerful enough to lessen that sense of losing bass energy. The T/9i – put simply – is your loudspeakers, but more so. Everything you like about your speakers is heightened; typically opening out the midrange detail, and adding a heightened sense of presence in the upper registers.
You would think, then, that adding a second T/9i would extend the bass and open out the midrange still further, and to an extent it does just that. However, the action of placing two well-engineered subs in the room seems to act on the room itself. A lot of the room-generated problems in audio fall into the sub 200Hz region, and typically require bass traps to tame the lower frequencies. These, it must be said, are often large and not what you might call domestically friendly. Placing an active device that works in precisely that sub-200Hz region that works to control that part of the output has a transforming effect on the sound of your system. And even two of them are small enough not to dominate the room.