My first draft of the intro for this review was rather witty, if I do say so myself. It lamented the fact that so many of today’s in-wall speakers are so good, it’s difficult to write something interesting about them. But I composed those opening paragraphs before I had actually listened to the speakers. Much as I hate to throw away a perfectly good intro, it would no longer do—because it was no longer true.

One could not consider Definitive Technology’s UIW RLS 2 in-wall speaker and IWSub Reference in-wall subwoofer to be ordinary products, even at first glance. Take the UIW RLS 2’s pair of passive radiators, which Definitive added to fix one of the biggest problems with high-quality in-walls: lack of bass. Like most high-end in-walls, the UIW RLS 2 has an integral enclosure, or back box. A back box improves fidelity because it keeps sound from the back of the woofer from entering the wall cavity, and thus keeps the wall from vibrating and producing its own sound. However, pressure that builds up inside the back box restricts the woofer and diminishes deep bass response. But the passive radiators relieve this pressure and use it to produce even more bass.

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The IWSub Reference incorporates an active driver that connects to the amp, and a passive radiator that reinforces the bass. (Click image to enlarge)

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Also, the UIW RLS 2’s slim front baffle increases mounting flexibility. Many in-walls are wide, so your installer can move them only an inch or two to either side before hitting a stud. With the UIW RLS 2, though, your installer can move the speaker several inches to the left or right. This characteristic is particularly important if the speakers are mounted behind a perforated screen. With smaller screens, it can be tough to cram left, center, and right speakers behind the screen without having to move a stud or two.

The IWSub Reference in-wall sub is even more unusual. Subwoofers are the final frontier of in-wall speaker engineering, because few good woofers are slim enough to fit into a standard 3.5-inch-deep wall. Plus, subwoofers demand a back box to perform well, and the back box takes up even more space. Definitive is among the first manufacturers who have risen to this engineering challenge. The IWSub Reference employs a 13-inch woofer that has been radically slimmed to fit in a wall; it’s such a tight fit that Definitive had to cut a hole in the back of the enclosure to accommodate the woofer’s magnet. A 13-inch passive radiator reinforces the woofer’s deepest bass notes.

A separate amplifier, the SubAmp 600, fits into your equipment rack. The SubAmp 600 is a stereo amp; it provides 275 watts to a single IWSub Reference, or 230 watts each to two IWSub References.

Does the UIW RLS 2 sound as good as the many excellent in-walls already on the market? No, it sounds better than most. If this speaker has a flaw, I cannot find it. (OK, the product name sucks. But besides that.) It sounds at least as good as any other in-wall I have tested, and given that I started evaluating these speakers regularly in 1995, I have tested quite a few. From the bass to the high treble, it sounds as uncolored as any speaker that comes to mind. I hear pinpoint imaging between the speakers, and the system wraps me in a huge, ambient soundstage. The UIW RLS 2 does not match the soundstaging of the best freestanding speakers, but it comes close—and it is far better in this regard than almost any current in-wall speaker I have heard, the MartinLogan Voyage and Thiel PowerPlane being its only peers.

The UIW RLS 2 also plays incredibly loud; I would recommend it for all but the largest home theaters. It produces enough bass that you can use it without a subwoofer in a smaller room. The only problem with the UIW RLS 2 is that I never want to stop listening to it; what I plan as hour-long evaluative sessions end up stretching well past my bedtime.

The IWSub Reference is certainly the best in-wall sub I have heard, even if it doesn’t reach the same level of perfection as the UIW RLS 2. It produces a surprisingly satisfying, full sound, even in my large home theater. And the sound is well-defined, too—the bass lines of my favorite rock CDs come through precisely, never boomy or bloated. The best freestanding subs sound a little punchier and can surpass the IWSub’s bass output, but the sonic sacrifice you get by going in-wall is in this case minimal.

On top of all this, both speakers are easy to install. Everything considered, I can think of no in-wall speaker system that matches this one’s versatility, sound quality, and value. I was going to call it amazing, but given that Definitive accomplished this fidelity with such straightforward engineering and at such an affordable price, it’s really beyond amazing.

DESCRIPTION
In-wall speaker system for home theater or stereo. Subwoofer employs separate 275-watt amplifier

COMPONENTS
UIW RLS 2: two 6.5-inch polypropylene cone woofers, two 6.5-inch passive radiators, 1-inch aluminum dome tweeter
IWSub Reference: 13-inch treated paper cone woofer and 13-inch passive radiator

CONNECTIONS
UIW RLS 2: spring-loaded binding posts, accepts bare wire, pins, or banana plugs
IWSub Reference: same as above
SubAmp 600: line-level inputs for left, right, and LFE channels; dual five-way metal binding posts for subwoofer out, main speaker in, and main speaker out

DIMENSIONS
UIW RLS 2: 29.8 x 8.2 inches (hw), 3.5-inch installed depth
IWSub Reference: 26.2 x 15.5 inches (hw), 3.5-inch installed depth
SubAmp 600: 3.7 x 17.1 x 9.6 inches (hwd)

PRICE/CONTACT
PRICE: UIW RLS 2 $650 each, IWSub $999 each, SubAmp 600 $599
CONTACT: 410.363.7148, www.definitivetech.com