KEF R700 loudspeaker Page 2

I also replaced the Integra pre-pro with my now-vintage but still pristine Jeff Rowland Design Group Consummate line-level analog preamplifier, driven by the analog outputs of the Marantz player.

The improvement in the bass was quite apparent. While the KEFs were still unlikely to satisfy headbangers, their bottom-end extension often surprised me. With Daft Punk's score for the film Tron Legacy (CD, Walt Disney D000567201), the KEFs certainly didn't sound like minimonitors with a pair of 6.5" drivers in a largish box thrown in for appearances. True, if you're familiar with how the gut-wrenching bottom end of the lossless BD soundtrack sounds with a good subwoofer (its score is the most gripping part of this otherwise mediocre film), you won't be all that impressed by the R700s. But if you're not, you'd be unlikely to think that anything was missing. The bass was as full-bodied and boom-free as you might expect from a heavily synthesized score. And the KEF's slight softness, referred to above and again below, was nowhere evident with this rather bright-sounding CD. The fuzz-box quality of the synthesizers was clearly audible, though thankfully less edgy than I've heard from other, brighter speakers.

914kef.white250.jpgThere's not much on the Tron Legacy CD suitable for judging the KEF's midrange quality, apart from the largely orchestral and beautifully handled final cut. But with other music I heard no obvious colorations, apart from a slight forwardness to voices. The midrange varied from recording to recording, of course, but I had no complaints at all about the way the R700 handled voices as dissimilar as those of Elvis, Jacintha, Sara K., Diana Krall, Willie Nelson, and Frank Sinatra.

Nevertheless, the bass limitations of the KEFs, as positioned in my room, were still sometimes apparent. The deepest drum whacks on Mickey Hart's Däfos (CD, Reference RR-12CD), for example, weren't quite there, though apart from that, the bass was crisp and free of boom. But with other recordings—such as Jim Brock's Tropic Affair (CD, Reference RR-31CD), or the thunder and drums of Rolf Smedvig's Hopper Dance, from the Empire Brass's Passage (CD, Telarc CD-80355, excerpted on Tag McLaren Audio's Test Tracks 01)—it was completely satisfying.

The R700s also produced a convincing soundstage. I'm fortunate in that my room has produced tight imaging and decent depth with dozens of speakers, source signals allowing, and the KEFs were no exception. Centered voices and instruments were so firmly positioned that I could have sworn a center speaker was installed (none was). Images at other points weren't quite as precisely delineated, but weren't pulled all the way to the left or right speaker unless recorded that way. Only rarely, however, did I hear a sense of anything to the left of the left speaker or to the right of the right. To be fair, in two-channel stereo this phenomenon appears to be dependent on rooms, setups, and recordings, and has been rare in my situation with any of the dozens of speakers I've heard in my current room.

The KEFs' slight forwardness did not diminish the way they handled soundstage depth. Not all recordings have significant recorded depth, of course, but with those that did, it was impressive.

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My main reservation about the KEFs was their subtle reticence at the very top end. This varied so much from recording to recording that a good argument could be made that the speakers were merely reproducing what they were being given. Bright material sparkled naturally, and only rarely did music sound too etched. But less lively recordings often sounded a bit airless, with leading-edge transients that seemed to be less than fully formed. I haven't seen John Atkinson's quasi-anechoic measurements (as I write, they have yet to be performed), but based on the measurements I've seen of other recent KEF designs, I'd be surprised if they weren't impressively flat. In a typical room, some treble rolloff is to be expected. My room is more highly damped than some, but my in-room measurements at the listening position, performed with the Omnimic2 system, do show a slightly more sloped taper from 1 to 10kHz than I've measured with other speakers I've recently reviewed for Sound & Vision and Home Theater magazines (Revel Performa3 F208, Monitor Audio Silver 10, Paradigm Monitor 11). The KEF R700s, in my room, leaned more to the forgiving than to the aggressive side, but were by no means dull—nor did their top end ever sound crass, or call undue attention to itself.

I then reinstalled the Integra pre-pro and drove the KEFs as a 2.1 system, with subwoofer. In any given room, the extension and uniformity of the bass is a crapshoot. No one can tell you what a speaker's bass will sound like in your room; a reviewer can describe only what it sounded like in his or her room. I positioned a Hsu Research VTF-15H subwoofer (I left one of its ports open, for those familiar with this product) midway between the left and right R700s, but closer to the wall behind them. Previous experience has indicated that this location offers relatively uniform response below 80Hz—the crossover point I intended to use.

Yes, the bass extended deeper, and the measured and audible in-room bass response was a little more uniform with the sub in the system. The bass of the KEFs alone was potent down to just below 40Hz, though with a notable dip centered around 50Hz, followed by a rise back up to the 40Hz level at 85Hz—clearly a room-produced dip/peak that added some audible warmth to the midbass. The dip did occasionally result in a dramatic difference. The kick drum on Aaron Neville's Believe (DVD-A, Silverline 288131-9I), for example, didn't, um, kick without the sub. But more often than not I didn't miss all that much the bottom-end extension offered by the sub—at least not with music—and only rarely were the midbass dip and peak bothersome. And the KEFs' top end was marginally more transparent without the sub; the Integra's Direct setting bypasses its high- and low-pass filter circuitry.

Conclusions
Only after finishing my listening did I go back to my notes and review of the larger KEF R900, which I reviewed last year for Home Theater (since merged with Sound & Vision). The similarities to the R700 weren't surprising, nor were the differences. I found both speakers a little short of air on top—I'd prefer a bit more sparkle and a crisper attack on the leading edges of transients. But for others, this slightly forgiving nature might well be a plus.

The imaging of both models is excellent, though a little more precise with the narrower R700s. And the larger R900 offers superior bass extension. I haven't heard the R500, but for smaller rooms I would expect it to be a worthy challenger for KEF's well-received LS50, for those who prefer a more conventional floorstanding design.

There's a lot of competition in this price range, but I wouldn't pull out my checkbook for another speaker before auditioning the KEF R700.

COMPANY INFO
GP Acoustics (UK) Limited
US: GP Acoustics (US) Inc.
10 Timber Lane
Marlboro, NJ 07746
(732) 683-2356
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COMMENTS
James.Seeds's picture

I know many manufacturers have a practice of doing this "Designed in the U.K, U.S.A or Canada and manufactured in China to the specifications of......."
Is KEF getting that much of a break on the labor costs and having them shipped by boat to North America, is it worth it to be associated with China?
At $3500.00 a pop is it not feasible to keep it in-house and take a slight hit on production costs, at the dealer they will be marked up by 50% anyway
My hobby is apparently supporting the PRC

shp's picture

I was looking forward to the new KEF R series. But as I read it, the review seems a bit qualified. A good speaker that's slightly idiosyncratic in its distribution pattern and sonic signature. I was waiting for something like "proper system matching is critical."

With a slightly rolled off high end and shallower bass extension, it seems like most tube amps wouldn't be the best match.

Is that a fair read?

raspeaker's picture

As a purely subjective observation from someone who used to sell KEF products, I think KEF has recently improved their speakers' reproduction of high frequencies. In the early days, KEF speakers sounded smooth and spacious but too rolled off at the top. I would not have bought them for myself. Some of the more recent models produced by KEF sound noticeably better to me in high frequency reproduction, however, and I have recommended these to others on occasion.

Bkhuna's picture

In a flash of inspiration..... that dawned on them decades after Tannoy did essentially the same thing.

John Atkinson's picture
Bkhuna wrote:
hat dawned on them decades after Tannoy did essentially the same thing.

The Tannoy driver was very different. It mounted the tweeter dome behind the woofer pole-piece and used the vented pole-piece and the woofer cone as a horn. The KEF driver mounts the tweeter on the front of the woofer pole-piece and while the woofer cone modifies the tweeter's dispersion, it doesn't horn-load the tweeter.

John Atkinson
Editor, Stereophile

Bkhuna's picture

Thanks for the lesson.

Oguz's picture

I bought this speaker one week ago after auditioned it against R500, Sonus Faber Venere 2.5, Monitor Audio Silver 8 and Focal Aria 936. I went to the store with the prejudgement of "bass shy" speaker but after auditioned all these speakers, I can say R700 has deepest and cleanest bass. It is also very well detailed. The only thing I did not like too much is treble performance which I hope it will get better after 50 hours of listening. I tested these speaker with my own Cambridge Audio 851W power amplifier.

Whitty's picture

Oguz, what about the treble response did you not like? Has the treble response improved after break in?

Oguz's picture

Yes, treble response has significantly improved. I am happy with R700 speakers.
I bought Hypex Ncore modules (NC400) and directly drive them with balanced output of Twisted Pair's Ivy III. The sound is not as musical as Cambridge Audio 851W but these modules drive R700 speakers more aggressively. R700 certainly likes power.

Whitty's picture

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