Castle Windsor Duke & Earl British-Made Loudspeakers

The Castle Windsor, previewed at last year's Munich High End Show, joins the latest versions of the classic Richmond and Avon models alongside the most recent Castle range, the Knights, launched in 2010.

The new Windsor series is the first Castle speakers to be UK-made in several years, thanks to parent company IAG's new 9,000 square foot production facility in Huntingdon. This sees every critical part developed and manufactured in-house.

Castle Windsor Earl

Moreover, the Castle Windsor standmount series has been designed by world-renowned speaker designer Karl-Heinz Fink and his FinkTeam, who are responsible for the Borg and Applause Award-winning KIM, amongst many other brands. In fact, Karl-Heinz has previous form with Castle as he was behind the Castle Richmond 3i in the early 2000s.

Castle Windsor Duke

The Windsor Earl is slightly smaller than the Windsor Duke (43x24x26cm Vs 47x28x31cm (HxWxD)), but both benefit from similar designs, such as the mid/bass cones (165mm in the Earl and 200m in the Duke), which are made from a polypropylene-based material. This is precision-cut into strips, woven and then bonded to form a solid foil. This is then pressed into shape and cut to size, resulting in a material with different rigidity properties at different directions between the voice coil and the surround. The company states this helps minimise resonances, creating a flatter response curve.

The cones' surrounds are made from low-hysteresis rubber, while the voice coils are made from glass fibre bonded with high-temperature resin. We're told that this material has a rigidity close to aluminium but without generating eddy currents to maintain signal purity.

The mid/bass drivers' magnet system also includes an aluminium compensation ring, which minimises impedance variations and reduces harmonic and intermodulation distortion.

The tweeters also benefit from classic engineering in the form of a high-consistency exposed polyester dome with a pressure-equalised ferrite magnet system and a metal front plate. No ferrofluid is used in the tweeter to guarantee the highest possible dynamic range, keeping the resonant frequency below 800Hz. In addition, the treble unit's 28mm voice coil includes a copper cap which Castle says reduces distortion and intermodulation, creating more detail.

Quoted frequency response (+/-3dB) for the Earl is 58Hz-22kHz, and the Duke 52Hz-22kHz, thanks partly to its 26L cabinet volume compared with the Earl's 15.8L.

Elsewhere, a thin layer of specially engineered acoustic glue separates the cabinet's MDF panels to dampen resonance in the midrange. Meanwhile, rigidity at lower frequencies is achieved by point-to-point cabinet bracing. In addition, both Windsor models use a 4th-order Linkwitz-Riley crossover, the Earl at 2.2kHz and Duke at 2.1kHz, which prevents distortion.

Castle's signature wood-veneer finish continues with the Windsors' cabinets sporting deep-figured walnut or mahogany veneers sourced from sustainable timbers - no reconstituted wood here.

The Castle Windsor Earl costs £3,850 per pair (£4,250 with stands), while the Windsor Duke is £4,500 (£5,000 with stands).

Visit Castle Acoustics for more information