An audio gargantua (with homage to Rabelais)
One of the venerable giants of home audio, the British company KEF recently celebrated its fiftieth anniversary in 2011 as a loudspeaker manufacturer. Founded by Raymond Cooke in 1961, the company was first housed at Kent Engineering and Foundry, or KEF for short. From the beginning Cooke had the foresight to experiment with new materials and technology – including the first to incorporate early computer testing – which led to significant advances in speaker design and manufacturing processes.
To commemorate the milestone occasion KEF introduced the LS50 Anniversary Model, a worthy successor to the legendary LS 3/5a. The LS50 Anniversary Model uses a single Uni-Q drive unit comprising of an aluminum tweeter derived from the company’s flagship Blade model, and a mid/bass driver similar to the ones used in their Q and R series. The Uni-Q coincident concept is one of several KEF innovations – a derivation from the original coaxial design pioneered by other speaker companies.
Product information, system setup and a bit more
This brings us to the subject speaker in review. The R300 is one of nine models in the KEF R series line of reasonably priced and affordable speakers. Retail price is one penny shy of $1,800 for a pair. KEF’s R series is below the Reference range but above their Q and C series in terms of cost and execution. The R300 is the larger of two bookshelf/stand-mounts while the other models in the range include three floor standers, two center channels, one dipole surround and one subwoofer. The entire R series was designed to be equally at home in a multi-channel video or two channel audio setup.
Because I have lived in an urban size apartment for a long time I have been interested mostly in relatively small to mid-size speaker systems. With dimensions of 15.2 x 8.3 x 13.6 inches the R300 fits nicely in my 18.5 x 14.5 x 10 ft living room. And its moderate weight of slightly more than 26 pounds was easy to lift and move around during the setup process without fear of getting a hernia. KEF does not make stands for this model so they sat on my Heybrook twenty inch tall metal stands with the Uni-Q driver firing horizontally at ear level.
KEF recommends initial set up of a minimum one meter (39 inches) from the side walls and a range of six to ten feet between the speakers. From that starting point and after some experimentation, I ended up placing the speakers approximately eight feet apart; with my listening position about eight feet in front and half way between them, essentially creating an equilateral triangle. Technically KEF recommends no toe-in because the tangerine waveguide on the tweeter diffracts the upper frequencies quite widely. Though experimenting is always good, I experimented with the speaker toe angle, from straight ahead to directly firing at the center. I experimented one degree at a time (all right, call me anal) and finally settled on about half way between no toe-in and my ear; creating a close facsimile to imaging I hear at most concerts.
The KEF R300 is a moderately efficient design (sensitivity at 88 dB, nominally 8 ohms) and the Music Reference RM-10 tube amplifier (35 wpc) used mainly for this review provided more than enough power to drive them to a thunderous loudness level. The Uni-Q coincident driver array consists of a 1 inch vented dome tweeter residing inside a 5 inch midrange. A separate 6.5 inch low frequency driver completes the three-way bass-reflex design (port in rear), with crossover points at 500 Hz and 2.8 kHz. To achieve lightness and stiffness all drivers are made of aluminum (the midrange driver is magnesium/aluminum), as well as the surrounds which are done in a nice brushed finish.
The company did a masterful job in creating an attractive and clean appearance with this series. Attention to detail is evident throughout as there are no visible driver mounting screws for instance. Another artful touch is the strategically placed KEF nameplate at the top center of the cabinet.
Single or bi-wire connections are provided by quality metal binding posts. In yet another example of tasteful design and engineering, there is a knurled knob to either join (clockwise) for single wiring or separate (counter clockwise) the crossover for bi-wiring. No more worry about where you misplaced the metal or wire link associated with some other brand speakers.
Two piece cylindrical foam port plugs (KEF calls them bungs) were also included with the speakers. The two foam pieces fit inside one another and the inner foam is easily removable. KEF recommends setting the R300 a minimum of 9 inches away from the back wall, and using the full plug at that distance. The company also recommends using just the outer plug if 1 ½ feet from the rear wall, and none if the speaker is two feet away or further. My final speaker position had the R300 two and a half feet from the back wall and I found bass output tight and articulate, so I didn’t use the port plugs. Please follow the recommendations as a starting point since no two situations are alike.
All models in the R series are now available in four cabinet finishes: Piano black, gloss white, walnut and rosewood. My review samples are finished in piano black. The rich finish of the cabinets has a nice sheen and luster, comparable to a fine automobile paint finish. Sans grill the R300 makes a strikingly bold statement of modern loudspeaker architecture. And sans grill is how I listened throughout the review period, though I re-attached them after each listening session for safety. The grills are magnetic and quite easy to remove and attach.
Some words on the enclosed owner manual. This is the first time I have seen a high end audio manufacturer solely using symbols and illustrations for informational communication rather than employing a descriptive narration. This approach relies more on logical and visual acuity than memorization of steps and procedures. With that said and after perusing what to me is a new approach, I have included several of the company’s installation recommendations which are scattered in the preceding paragraphs.
Associated equipment for this review included my trusty Rogue Audio 99 Super Magnum preamplifier and Music Reference RM10 tube amplifier. For comparison, my AAD 2001 stand-mounted monitor speakers were called up for duty. I have always enjoyed the sound of AAD speakers, which are designed by another well known Englishman, Phil Jones. An OppO 981 player acted as the deejay spinning tunes (both CD and SACD), which was connected to either a B.M.C PureDAC or a highly modified Art D/IO DAC for interpreting the jingles. All cabling is by Audio Sensibility (a true bargain), except the power cords which are Triode Wire Labs (another bargain) and Supra Cables.
- (Page 1 of 2)
- Next page →