The Reference series has always been KEF’s most high-end products, although there are also Muon and Blade series. But Muon and Blade are more like conceptual fantasy products, and they are ridiculously expensive. The Reference series is market-oriented, and best represents KEF’s core technology. KEF released the first generation Reference series 1973. It has gone through several generations so far, and the appearance has changed greatly. That means that for KEF, each generation change is a major technological innovation.
KEF was founded in 1961 by Raymond Cooke, a former BBC electrical engineer, with several business partners. It was originally headquartered in a shed at Kent Engineering & Foundry in the United Kingdom. KEF is named after. Since its inception, KEF speakers have conquered the industry with its pioneering and innovative capabilities. Today, KEF, which has been developed for over half a century, is still highly regarded by high-fidelity enthusiasts worldwide with its innovative high-performance speakers.
KEF’s Reference is a long series, from 1973 to the present, through 9 generations of product innovation. The Reference series is KEF’s products in each flagship period, showing KEF’s latest advanced technology.
Reference, the name comes from the inspection method of the speaker product line. Each assembly process of the Reference speaker must be strictly tested. The final product must be compared with the laboratory’s reference standard to ensure consistency with the laboratory standard quality. Reference represents the pursuit of ultimate movie sound effects and high-end music enjoyment. Many brands will use this term for advertising their flagship models.
The reference series includes a bookshelf speaker, floor speaker, center speaker, and subwoofer. The entire series can form a complete multi-channel system. Reference 1 is the only bookshelf speaker among them.
As KEF’s top product, the core technology is Uni-Q coaxial technology. Since the 1980s, Uni-Q technology has been applied to the Reference series and fully recognized by the market. In engineering terms, multi-directionality is called “Q,” and the name Uni-Q means uniform directivity. Reference 1 uses KEF’s newly developed and most powerful mid/high-frequency coaxial unit. The unit consists of a 25mm (1 inch) aluminum dome tweeter installed in the center of a 125mm (5 inches) midrange unit.
In a traditional two-channel system, the midrange unit and the tweeter unit are installed separately. Since the mid-frequency and high-frequency are generated at different drivers from different positions, forming a phase difference, the image may be blurred and cannot achieve fidelity sound effects. Uni-Q technology accurately installs the mid-bass and tweeters at the same point in the speaker, so that high-frequency and low-frequency can be emitted from the same point, ensuring a more precise image. At the same time, the sound output of bass and treble can be calibrated in all directions. Therefore, Uni-Q breaks the vertical interference between the separating bass and tweeter, avoids the bass and treble crossover situation, and reduces the sound’s distortion.
Secondly, because Reference 1 uses Uni-Q technology to overlap the two driver units, the tweeter can be adjusted to almost the same directivity as the mid-bass unit. Whether horizontal or vertical, when the listener is far away from the speaker’s main sound axis, the entire listening area’s tonal balance is not different. The speakers are not very picky about the room environment and can be well integrated with various rooms. With complete mid-range maintenance, listeners sitting in an off-axis position or even on the listening room’s side can hear a good stereo effect.
To summarize, the advantages of the Uni-Q coaxial unit:
- More natural sound
- More accurate time phase
- Clearer sound
- A wider listening area
- Lower distortion
- Easier to integrate with the room
Reference 1 uses a newly designed 165mm (6.5 inches) aluminum woofer. The aluminum cone has a lightweight and high rigidity characteristics, coupled with the large-size voice coil and the good ventilation performance of the magnetic steel, to ensure that the heat can be quickly dissipated. Careful attention will find that the woofer’s hemming is not a common convex structure, but concave hemming. This design can further enhance the carrying power of the unit to obtain a faster transient speed.
The magnetic circuit components of the woofer have been newly designed. KEF uses a large magnetic circuit system that allows the entire voice coil to maintain a uniform magnetic field and consistent magnetic force in the path of motion. The distortion problem caused by the uneven magnetic field of the ordinary voice coil is solved, and an ideal and uniform magnetic field environment is provided for the voice coil. With the special aluminum wire voice coil for the unit to drive an ultra-light and strong alloy cone, no matter what kind of music is played, the woofer can perfectly match the Uni-Q coaxial unit.
What is the performance of the 6.5-inch woofer used in Reference 1? KEF claims that the dive of Reference 1 is 40Hz, and the lowest indoor frequency is 30Hz-6dB. I did a test. If the sensitivity of 85dB can be matched with a power amplifier of more than 200 watts, or a tube amplifier of more than 100 watts, this little giant will instantly become a big monster!
KEF Reference 1 weighs up to 18kg, which is also relatively heavy as a bookshelf speaker. The front baffle has a smooth texture and is made of super-strength aluminum and resin composite materials for three-dimensional cutting at extreme temperatures. The use of super sound-absorbing pads and high-strength bolts enhances the box’s rigidity and reduces the impact of bad reflections and excessive resonance on the sound. The cabinet is made by hand with matched wooden veneer panels. The shape and the interior are optimized and designed through precise calculations, and combined with sound-absorbing materials. The residual vibration is absorbed by multi-layer damping to eliminate unwanted resonance, scattering, and sound stain.
In addition to the luxurious configuration from inside to outside, the exterior design of Reference 1 is also remarkable. Reference 1 has 3 colors to choose from: Copper Black Aluminium,Blue Ice White and Silver Satin Walnut. No matter which finish can reflect the high-end and gorgeous temperament of the speaker.
Reference 1 uses KEF’s exclusive flexible inverter technology on the bass port. It provides two inverters’ lengths to fine-tune the bass output to meet other users’ tastes and listening space needs. There are two sizes of the port supplied – the short tube gives a low-frequency reach of 40Hz and the longer 37Hz. KEF said its main technology comes from the award-winning LS50 worldwide. KEF uses computational fluid mechanics principles to design the bass port with the most appropriate curve and structural appearance. It can prevent turbulent airflow and avoid longitudinal resonance pollution and sound.
Below the bass hole is a two-wire terminal that can connect two amplifiers at the same time. Although few people use Reference 1 like this, it also shows that KEF has designed the Reference series with the ultimate attitude. The small knob in the middle of the treble and bass binding posts is acting as a bridge. A single amplifier can be adopted to drive it by turning it clockwise to avoid using an external bridge to affect the sound quality.
To make the best use of The Reference series units, KEF designers also optimized the crossover design. They use the computer to model and analyze the crossover network and carefully select each component to make the unit optimal for the lowest distortion in the frequency range. Reference 5 and Reference 3-floor-standing speakers are equipped with a specially designed stand. The Reference 1 bookshelf box, The Reference 2c, and The Reference 4c center speakers are also equipped with a dedicated stand. Each speaker is combined with metal adjusting feet, allowing The Reference series of speakers to fulfill their inherent potential better.
Reference 1 is a bookshelf speaker, the sound field it creates will not be exaggerated, and you can thoroughly feel the natural three-dimensional space. The images are vivid and three-dimensional. KEF Reference 1 controls the rhythm. The undulating sections are calm, clean, and without procrastination, the dynamic rise and fall are stable, and the music feels vibrant and lively.
The mixed-material front panel of Reference 1 gives me a sense of robustness, and its sound also fits this criterion. KEF Reference 1 doesn’t have too many low frequencies, it doesn’t have bloated mid-range, and it doesn’t over highlight the high-frequency range. Music sounds balanced and natural, without burden. Reference 1 has the translucent and real sound that Hi-End speakers often have.
The low frequency is very beautiful. The style is neutral and natural, with high density and fullness. The low frequency is the one that attracts me the most. The low frequency is not large, but it makes me feel shocked and has a good dive without unnecessary and unnatural rendering, just pure instrument restoration.
Dynamic and Powerful
In large scenes that require huge momentum, Reference 1 can also reproduce the music well. The volume fluctuations are just right, and the dynamics are handled properly. The low frequency does not become muddy even at higher volume, maintaining a consistent sense of transparency. The powerful low frequency and high energy pose a big challenge to the bookshelf speaker, and Reference 1 has achieved it.
The sound of Reference 1 is transparent and bright, while the midrange is warm. High density and fullness are significant advantages, which makes the listener more engaged. The room where I listen to Reference 1 is small. Still, the sound field can also be heard very wide. The image is delicate, the instrument positioning is clear, it is very three-dimensional, and the image’s height is also very reasonable. In the big scene symphony, Reference 1 can also maintain a stable performance, and the positioning and density still maintain a high level.
As the flagship series of KEF, it has gathered all the technical essence of KEF so far, and Reference 1 has played the flagship standard. The Reference 1 voice also escapes the limitations of the speaker on the bookshelf. Reference 1 is already very satisfactory. The sound of Reference 1 is balanced and neutral. If the types of music you listen to are more varied, then the versatile Reference 1 will be a very suitable choice.
KEF Reference 1 Specs
- Design: Three-way bass reflex
- Drive Units: Uni-Q driver array,HF: 25mm (1in.) vented aluminium dome/MF: 125mm (5in.) aluminium, Bass units:LF: 1 x165mm (6.5in.) aluminium
- Frequency range free field (-6dB): Short port: 40Hz – 45kHz/Long port: 37Hz – 45kHz
- Frequency range typical in room bass response (-6dB): 30Hz
- Frequency Response (±3dB): 45Hz – 35kHz
- Crossover frequency: 350Hz, 2.8kHz
- Amplifier requirements: 50 – 200 W
- Sensitivity (2.83V/1m): 85dB
- Harmonic distortion,2nd & 3rd harmonics (90dB, 1m):<0.5% 40Hz – 100kHz/ <0.2% 200Hz – 10kHz
- Maximum output(peak sound pressure level at 1m with pink noise): 111dB
- mpedance: 8Ω (min. 3.2Ω)
- Weight: 18.2 kg (40.1lbs)
- Dimensions – with grille and terminal (H x W x D): 440 x 205 x 430 mm/ (17.3 x 8.1 x 16.9 in.)
- Finish: Copper Black Aluminium,Blue Ice White, Silver Satin Walnut