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Castle Acoustics Knight 4 Floorstanding Loudspeakers Castle Knight 4s in great condition - a very tidy pair that has been very well looked after. No noticeable scuffs or scratches, grills are pristine, surrounds are in great shape and have no signs of wear. 25 -150w @ 8omhs 90db sensitivity 36hz - 24khz 900mm tall on spikes 12.5kg a piece They sound amazing, great detail and a wide sound strange for their size. Perfect for an apartment or medium sized room. They pair very nicely with warm vintage gear to my ear and are easy to drive. They stand on steel floor spikes with little rubber cushions
At A$750, this Castle Knight 4 listing is a strong deal, sitting well below the typical used market where similar pairs trade around A$550–A$650 in the UK (≈A$1,050–A$1,250 new, with used often £295 ≈ A$570) and A$1,450 when sold by a new Australian seller recently. The asking price is below the 25th percentile of current used listings, making it a genuine bargain for a floorstanding speaker that still delivers the classic British sound, easy 90dB drive, and deep 36Hz bass response.
These speakers are well-regarded for their slim profile, down-firing port that allows wall placement, and high wife-approval factor, while including original jumpers and spikes. As a 2010-era model now replaced by newer Knight ranges, finding them in unknown condition at this price is a timely buying opportunity for enthusiasts seeking value without sacrificing performance or aesthetics. No caveats are needed here—the price alone makes this a low-risk, high-upside pick.
Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.
Castle Acoustics, a revered British loudspeaker brand, traces its origins to September 3, 1973, when it was founded in the North Yorkshire market town of Skipton by William "Bill" Escott and John Collinson. Both veterans of Wharfedale—and Collinson also of Quad—these engineers established the company in an old woollen mill, drawing its name and logo from the historic Skipton Castle. From the outset, Castle emphasized complete in-house production, crafting drive units, electronic components, and hand-veneered wooden cabinets under one roof, setting it apart in the 1970s hi-fi landscape.
The brand has steadfastly focused on high-fidelity loudspeakers, eschewing diversification into amplifiers, turntables, DACs, headphones, or cables. Iconic models like the Howard, Harlech, Durham, Pembroke, and later Knight series exemplify its commitment to premium wood-veneered enclosures, woven carbon-fiber bass drivers, and cutting-edge acoustic engineering. Acquired by the International Audio Group in 2007, Castle has expanded into home cinema while preserving its two-channel heritage.
Positioned as a high-end boutique manufacturer, Castle commands respect among discerning hi-fi enthusiasts for its "no compromise" sonic performance, furniture-grade craftsmanship, and timeless musicality. Award-winning designs, such as the Knight series lauded by Hi-Fi Choice and Hi-Fi World, underscore its enduring appeal in the premium market, blending British tradition with modern innovation.
See all Castle Acoustics listings on RADAR.
