John Darko
Chinese conglomerate IAG has resurrected the Castle brand of loudspeakers for the UK production of two new high-end standmount loudspeakers. The all-new Windsor Earl (43 x 24 x 26cm) and the slightly larger Windsor Duke (47 x 28 x 31cm) will be made in the same Cambridgeshire factory as the Mission 770 and the Wharfedale Dovedale. However, the designer this time around isn’t Peter Comeau but Karl-Heinz Fink — he is the brains behind the Castle Richmond 3i, released almost twenty years ago and, more recently, the Wharfedale Diamond 12 Series.
The new Windsor Series’ mid-bass drivers – 16.5cm in the Earl and 20cm in the Duke – are made from a polypropylene-based material that, according to the press release, has been “precision-cut into thin strips, woven back into a sort of fabric, and bonded together again to form a solid foil. This foil is pressed into the final shape and cut to size. This is a much more complex way of creating a polypropylene cone, but it has significant sonic benefits. The process creates a material with different properties of rigidity, at different directions between the voice coil and the surround. This helps to minimise resonances, which produces a flatter response curve – a desired characteristic of any drive unit designed for high-performance audio.”
(Bass reflex ports fire to the rear.)
Each Windsor’s tweeter is a 28mm polyester dome backed by a “pressure-equalised” ferrite magnet system and contains no ferrofluid, reportedly for superior dynamic range and a lower sub-800Hz resonant frequency.
On the crossover, Fink and his team went with a 4th order Linkwitz-Riley design that was developed with a combination of computer modelling and listening tests — according to IAG, the aim was to produce a crossover circuit that gave the flattest response but also presented an easier load to the amplifier.
Back to the press release: “All critical inductors in the crossover design are of the ‘air core’ type – this means there are no metal cores present in the circuit, preventing hysteresis or distortion through the network. The main inductor resistance is compensated in the mid/bass driver’s magnet system, so there is no disadvantage from the slightly higher resistance of this air coil.”
Each Windsor standmount’s drivers and crossover are housed in a cabinet made from dual-layer MDF that are separated by a thin layer of acoustic glue that was developed to dampen unwanted midrange resonances. Point-to-point bracing rounds out the cabinet design with the walnut or mahogany veneers being book-matched and hand-waxed to a mirrored finish.
Pricing? £3,850 for the Windsor Earl and £4,500 for the Windsor Duke. Open-frame speaker stands are available for each model: £400 and £500 respectively.
Further information: Castle
