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Authorized KEF Subwoofers Repair Service Center
We are an authorized KEF subwoofers repair service center. Providing KEF subwoofer repair in and out warranty in
Minneapolis and St Paul Minnesota. We repair Vintage Stereo, AV Receivers, Amplifiers, Power Amplifiers, Integrated
Amplifiers, Preamps, CD Players, CD Changers, Stereo Receivers, Powered Speakers, Tape Recorders, Tuners and
When KEF was founded in 1961, by Raymond Cooke and a small group of like minded colleagues, the prime objectives
were to design loudspeakers using the latest materials technology and with the best engineering methods. The 1960s was a
hotbed of innovation in drive unit technology with significant contributions from a number of commercial companies as
well as the BBC’s Research and Design departments.
The first drive units designed and developed by KEF formed the K1 series of products. They comprised the B1814 bass
unit, with a flat diaphragm of polystyrene with aluminium foil laminated to the front and rear surfaces, the M64 elliptical
midrange with the same polystyrene/aluminium foil laminate structure, and the T15 tweeter with a dome made from
aluminized melinex. The early brochures make a point of emphasising that all drive units in KEF loudspeakers have
diaphragms of synthetic materials.
Most loudspeakers at the time had diaphragms made of paper compounds, which could suffer from sound colouring
resonances, sensitivity to climatic conditions and batch-to-batch variations in production; and the thought was hat plastic
materials ought to offer significant advantages. The fact that bextrene and later polypropylene came to dominate the
market for serious Hi-Fi drivers pays tribute to this vision.
Credit ought to be given also to those who continued to develop the technology behind paper and fabric diaphragms as
they now have an equal standing with plastics and metals in high-end audio. Hot on the heels of the B1814 came the B139
(13 by 9.25 inches in size), probably the most famous of the KEF drive units. Again the diaphragm was polystyrene with
aluminium foil laminated to the front and rear surfaces. Its midrange performance was just about good enough to integrate
directly with the T15 tweeter allowing the K2 series of 2-way products to be designed including the Celeste and Duette.
KEF C4 Subwoofer
Unobtrusive, handsome and powerful, the C4 subwoofer delivers incredible bass while
maintaining control throughout its range.
With a 200W on-board amplifier driving a 200mm (8in) front-firing bass cone, the C4 is
engineered to minimize distortion and add effortless depth and weight to any
Powered bass reflex subwoofer
Drive Units: 1 x 200mm (8in.) LF
Frequency Response: 29Hz - 140Hz , 200W built-in Class D amplifier
Dimensions: 345 x 320 x 377 mm (13.6 x 12.6 x 14.9 in.), Weight: 27 lbs.
Finishes Available: Classic Black Ash
We guarantee our COD parts and labor for 90 days. Warranties apply to the original repair only, physical damage, shorted outputs
in Stereo, abuse, power surge, lightning, are not covered. Original manufacturer warranty applies.
Powered Speakers and Subwoofers Repair