The KEF R Series is the British speaker-maker’s first collection of loudspeakers to integrate some of its most recent innovations, principally those in the ground- breaking $30,000 Blade (Issue 222). A family of nine transducers, all easy on the pocketbook, the R Series includes a threesome of floorstanders, a pair of stand-mounts, two center channels, a surround, and a subwoofer. My first exposure to the R Series occurred at the Axpona Show in Jacksonville earlier this year, where the Rs were alternating with the stunning Blades in a lobby- level conference room. The room was like a small auditorium—a formidable challenge for any loudspeaker. Due to my fondness for compacts my eye naturally gravitated toward the silent R-300s parked to one side. I asked to hear them and KEF’s genial gents assured me they’d be demo’d later that day. I was so impressed with this three-way design and its distinctive Blade-derived coincident driver that I put in my request for review samples on the spot.
For the record, the $1799-per-pair R-300 is a three-way, bass- reflex compact, roughly fifteen inches tall. The piano-black exterior brilliantly sets off the aluminum diaphragm of the Uni-Q concentric, the cynosure of KEF’s transducer technology. It’s a tweeter/midrange array wherein the vented aluminum-dome tweeter is positioned at the acoustic center of the midrange cone.
The tweeter is outfitted with a large neodymium magnet and a computer-optimized dome structure. As in the Blade, mounted directly above the dome is KEF’s segmented “tangerine” waveguide, which further aids the dispersion of high frequencies over a wider off-axis field. Handling the midband is a braced magnesium/aluminum alloy cone with a die-cast aluminum chassis designed to minimize resonance-transfer to the cabinet. The low-profile, almost invisible surround is KEF’s Z-flex design, which maintains smooth, linear transmission of reflected output off the baffle. The bass driver uses a combination of a vented- magnet assembly and a large, lightweight, 2" aluminum voice coil driving a light, stiff hybrid-cone. Like the midrange driver, the woofer makes use of a Z-Flex surround and an outer, flat-profile trim ring. The crossover points are 500Hz and 2.8kHz.
Visually the front baffle is immaculate. It’s been laid out so that each driver is flush-mounted with the front panel, the baffle itself devoid of visible driver-mounting screws. Even the grilles affix magnetically. The enclosure is constructed from MDF. The front baffle is a robust 32mm thick, while the other panels and braces are 18mm thick. Constrained-layer-damping pads are strategically placed internally. At these select locations the cabinet expands its thickness to around 24mm. Computational fluid dynamics have been used to optimize airflow through the reflex ports.
The R-300 is bi-wire/bi-amp capable, but single-wire fans needn’t fret because there’s a pair of knobs on the back panel for splitting or rejoining the crossover when running the speakers in either bi-wire or single-wire modes. Just turn each knob clockwise to link the treble and mid/bass drivers or counterclockwise for bi-wiring. No jumpers required. Impressive housekeeping, KEF.
The sonic signature of the R-300 can be summarized in a few words—precision, pitch, forward, and focused. Its tonal balance conveys a smooth, slightly gung-ho midrange bias with little in the way of significant energy droops or peaks. Bass reproduction is rock-solid into the midbass. There’s a bit of dryness and brightening in the treble underscored by a slight loss of energy in the upper mids. It’s a factor I noted with specific singers—a cappella artist Laurel Massé on Feather & Bone comes to mind—as they transitioned from lower to upper octaves. The R-300 creates a more laid-back sound. And if you’re scoring, it’s a minor deduction. On the other hand, the three-way configuration gives the speaker a warmer and more dynamic midrange balance, and that warmth and dynamism extend into the lower mids and upper bass, where, to my ear, this little bit of enrichment makes the R-300 sound like it has slightly more low-frequency extension than it actually possesses. Midrange dynamics are especially lively. This is an area where most two-way compacts tend to sound a bit subdued at higher listening levels. Bottom-octave dynamics are not quite as lively but still pretty darn impressive. Extension is very good into the 50Hz range, with only a hint of added bloom from the port.
Image focus is wonderfully precise—not as surgical or transparent as the TAD CR-1, mind you, but taking a back seat to that $37k wonder is nothing to be ashamed of, either. One of the best pop records to illustrate this focus is Steely Dan’s Gaucho [MCA]. It’s pure crackling musicianship, with pitch- perfect engineering courtesy of Elliot Scheiner and Bill Schnee, and mastering by Bob Ludwig—nihilistic-hipster songcraft at its finest. From the opening strains of “Babylon Sisters” and “Hey Nineteen,” the R-300 could have been holding a clinic for midrange timbre, focused imaging, and dynamic, iron-fisted bass. Similarly spotless imaging was apparent during Wellingtons Sieg [Turtle]—a piece that builds in intensity from the distant battle snares to the bugler’s call springing from various soundstage locations. Not unexpectedly, the steady volley of bass drums ultimately did compress somewhat, and with it went some of the finer timbral distinctions, but in the right room (not too big), prepare to be impressed. Make no mistake—this is no Blade. In comparison, the R-300 is more Penknife. But as it repeatedly showed during some heavy rock tracks, it’s more than happy to reveal its inner badass.
The R-300 conveys tonal and timbral colors that are exceptional in this price range. For example, it captures the humid and darkly haunting character of Lyle Lovett’s “Baltimore,” while the opening piano intro of “North Dakota” has the harmonic hallmarks of live piano—the speed and, more importantly, the timbral accuracy. This track can sound icy and synthetically hard, but the R-300 delivers a piano that has the weight and physicality of an actual instrument.
With solo piano the R-300 consistently revealed the nuance and sensitivity of the player’s touch on the keys. It was equally informative about other low-level cues, and about the fine gradations of dynamics that allow musicianship to envelope and immerse. The bottom octave was more representative than authentic, but the woofer integrated well with the coincident array, betraying only small hints of its partnership with the rear-firing port.
The R-300 gives up little in the way of transparency in most circumstances but under the full weight of a pianist’s hands, multiple-note passages that include explosive chords, lightning trills, and laser-guided arpeggio lines can sound a bit amorphous, and the R-300 doesn’t always fully organize the rush of trailing harmonics left in the wake of this flood of activity.
Sonically, the success of the R-300 rises and falls on the performance of the coincident-driver technology that has all but defined KEF for decades. Here there is none of the shouty, “cupped-hands” coloration that early coincidents were often guilty of. Nothing’s perfect, however. I noted a bit of added honk during Tom Scott’s sax solo on the aforementioned Gaucho. However, I found the Uni-Q-equipped R-300 was at its most insightful reproducing the human voice—the instrument most familiar to all of us. On a variety of vocals, my impression was not just one of focus, which the R-300 has in abundance. Unscientific as this may sound, a singer’s voice achieved a unity, a oneness, on an almost subconscious level that most compacts in this range can’t quite muster. Normally, at some point during a performance, I have the minute impression of listening to separate drivers—a hint of blur, like failing to line up a photographic image in the crosshairs of a camera’s focusing screen. Not with the Uni-Q. It’s a terrifically coherent speaker with unimpeachable driver integration.
I hope I’ve made it clear by now that, despite all the fuss surrounding the Uni-Q coincident array, the R-300 is no one- trick pony. It’s a really stirring, all-around performer that enlivens the mix in this competitive price segment. I’ve only one thing to add: Where were you, R-300, when I was just starting out as an audiophile?
SPECS & PRICING
Drivers: Uni-Q (1" dome, 5" midrange, 6.5" woofer)
Frequency response: 50–28kHz
Impedance: 8 Ohms
Dimensions: 15.2" x 8.3" x 13.6"
Weight: 26.4 lbs.
GP ACOUSTICS (U.S. distributor)
10 Timber Lane
Marlboro, NJ 07746