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Kef XQ40 Tweeters I have a pair of XQ40 speaker both with distorting tweeters. They were originally not working at all, after dismantling I had found wires from the diaphragms had broken at the solder joint. After resoldering they sounded fine for a while but now distort. I replaced the ferrofluid but that hasn't helped. I found new diaphragms on eBay that supposedly were to suit these speakers but the voice coils are too short so they don't enter the magnet enough if at all and are very quiet. I contacted the Australian Kef distributor but they don't have any spares. Part No: XQ MK2 SP1
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KEF traces its roots to 1961, when British engineer Raymond Cooke founded the company in a modest Nissen hut on the grounds of the Kent Engineering and Foundry in Maidstone, England. A former BBC engineer and Wharfedale veteran, Cooke was driven by a passion for music and a commitment to technological innovation, aiming to reproduce sound as faithfully as the original performance. From its inception, KEF pioneered materials like foil-stiffened polystyrene diaphragms and Melinex tweeters in its debut K1 loudspeaker, setting a benchmark for engineering precision that propelled the brand to early acclaim.
KEF has long specialized in loudspeakers, establishing itself as a leader with iconic innovations such as the Uni-Q coaxial driver and computer-aided design techniques that revolutionized driver and enclosure development. While drive units supplied to other manufacturers fueled its growth, the brand's core output remains high-fidelity speakers across categories like floorstanders, bookshelves, and home theater systems, including early THX-approved setups. Active wireless models and reference-grade series extend its portfolio, though it eschews amplifiers, turntables, DACs, headphones, or cables.
Renowned for its science-driven heritage, KEF occupies a premium position in the hi-fi market, blending accessible high-end performance with cutting-edge technology. Collectors prize vintage BBC monitors and Bextrene-driver classics, while modern buyers seek its precise, natural soundstaging. Decades of awards affirm KEF's status as a respected innovator, appealing to discerning audiophiles who value engineering over hype.
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