The Q300 is the top of the updated Q-series of loudspeakers from KEF. According to the company tradition, their 2-way configuration is implemented with a single speaker – the coaxial module Uni-Q with a diameter of 165 mm. The cabinets are acoustically designed as front-port reflex units. Bodies are made of MDF, seems to be covered with real wood veneer, but it’s not exactly true, a coating of recycled wood fibers is used, preserving the color and texture of the real veneer. KEF keeps it eco-friendly and offers three different finishes: black oak, cherry and walnut.
CONSTRUCTION
The new Uni-Q coaxial module uses technology from the Blade concept design and a larger tweeter dome with a diameter of 25 mm previously the size was 19 mm . The result is more tweeters, a wider dispersion pattern and a narrower MF bandwidth, making it easier to match a tweeter with the midrange.
The membrane structure is borrowed from the “older” speakers KEF, used “double” dome, only made not of titanium, as in the Blade, but of aluminum. The membrane is a nested domes of spherical and elliptical shape, which greatly increases its strength and resistance to resonances. The tweeter is surrounded by the proprietary Tangerine Waveguide “acoustic lens”, which controls the dispersion of sound, further enhancing its directivity.
KEF’s Tangerine multi-bladed splitter was born a few years ago, following research into the audible resonances that occur at the mouths of compression tweeters, but further experiments have shown that tweeter placement into shallow waveguides can cause damage of a similar nature.
The new Tangerine is optimized precisely for use with the tweeters of the coaxial modules of the upgraded Q-series. Like the Reference and Blade tweeters, the tweeters are fitted with a long damping tube. The tube is closed at the far end and filled with a sound absorber, its purpose is to reduce air compression in the chamber behind the diaphragm, reducing sound distortion, especially at high volume.
SOUNDING
The midrange diaphragm of the Uni-Q module is made of lightweight, rugged aluminium, which can be effortlessly shaped. The diaphragm and surround have a specially designed profile, derived from computer modelling and ‘live’ experimentation as they are not just part of the midrange driver but also the outer perimeter of the tweeter waveguide, so their resonances will affect the upper frequencies.
KEF’s engineers are working with midrange resonances in a very ingenious way: the Cone Breakup Control technology incorporates a special bond between the voice coil and the diaphragm, which is rigid for the lower frequencies of the speaker’s bandwidth, but resists higher frequencies by absorbing system resonances.
The outer surround of the midrange diaphragm is called Z-Flex, and has an unusual radial ribbed pattern that allows sufficient freedom of movement in and out of the diaphragm to give it relatively long stroke. And Z-Flex’s proprietary design allows only low frequency modes of vibration, suppressing any mid frequency resonances that might be transmitted to the driver diaphragm.
Both Uni-Q transducers have upgraded magnet assemblies with increased wattage. For better control, the midrange drivers use large-diameter voice coils 50mm and a length that far exceeds the magnetic gap, so that even when the cone excursions are at their maximum, the coil stays in the gap. Large coils made of copper would have been too heavy, so the designers used aluminium.
Careful optimization and selection of the characteristics of the speakers of different bands pays off also because the developers were able to use in the speakers Q-series simple separating filters of 1st order, bringing minimal phase distortion in sound. Minimalist to the point where there is one capacitor in the tweeter crossover and one inductor in the midrange circuit.
Q-Series innovations include even terminal strips. Surely inveterate audiophiles have experienced the property of jumpers to constantly get lost, KEF have solved the problem once and for all, “sewing” the terminals inside the panel. They are now placed in and removed from the working position with the help of two twist handles. The terminals themselves are conventional, gold-plated, allow the user to connect the speakers in two cables and experiment with Bi-Wiring/Bi-Amping.
SUMMARY
The Q300s have lost some of the elegance of their predecessors without the beautiful curve of the side panels. But KEF’s designers felt that rectangular forms were not only more practical because they gave up to 30 per cent more internal volume, which makes it easier for the bass driver to work, but also conformed to current trends in “high style” furniture design.
The cabinets are made of MDF, seems to be covered with natural veneer, but it’s not quite true – a coating of recycled wood fibers is used, preserving the color and texture of real veneer. KEF has underlined the sustainability of this approach and offers three different finishes: black oak, cherry and walnut.
32 400 Dollars.
Can you please share your thoughts and experiences with the floor-standing speaker system 2.0 KEF Q300? How would you rate its sound quality, design, and overall performance? Any pros or cons worth mentioning? Thank you!