Castle Acoustics unveils two new Windsor speakers Earl and Duke
Castle Acoustics unveils two new Windsor speakers Earl and Duke

Castle Acoustics unveils two new Windsor speakers Earl and Duke

The famous British speaker brand Castle Acoustics has introduced new acoustic models in the Windsor series – Earl and Duke . Since its founding 50 years ago, Castle Acoustics has become renowned for the superior quality of its handcrafted speaker cabinets and the ability to manufacture key speaker components in-house rather than outsourced.

The current Castle range includes a variety of speakers, including the latest versions of classic Richmond and Avon models, but since the Knights in 2010, there have been no new Castle ranges. And so the company introduced two models of speakers, Earl and Duke, forming a new series of Windsor. Their cabinets of classic proportions, finished with natural wood veneer, are reminiscent of the golden age of Hi-Fi.

As is traditional with Castle Acoustics, every element of the two new Windsor models has been designed and manufactured in-house, from the drivers to the cabinet and crossover. In addition, these are the first Castle speakers in many years that are not only designed but also manufactured in the UK.

Castle Windsor Earl is the smaller of the two models, while Windsor Duke is larger in all three dimensions. The novelties are made in a two-lane configuration. Both Castle Windsor models are equipped with polypropylene-based mid/bass drivers. However, instead of being produced by simply vacuum forming foil, polypropylene is cut into thin strips, woven back into a kind of fabric, and glued together again to form a solid foil. This foil is given its final shape and cut to size. Cones with a diameter of 165 mm on the Windsor Earl and 200 mm on the Windsor Duke have low hysteresis rubber surrounds. The voice coil cores are made of fiberglass bonded with high temperature resin. The rigidity of this material is very close to aluminum, but it does not create eddy currents,


The midrange/woofer magnet system includes an aluminum compensation ring to help minimize impedance fluctuations during operation. As a result, harmonic and intermodulation distortion values ​​are reduced.


The tweeter used in both Windsor models features a high-consistency polyester dome cone, a pressure-equalizing ferrite magnet system, and a metal front plate. The tweeter does not use ferrofluid. The voice coil of the high-frequency transducer has a diameter of 28 mm and is equipped with a copper cap on the pole piece of the magnet.

The construction of the Castle Windsor cabinets uses two-layer MDF panels separated by a thin layer of a specially developed acoustic adhesive. This adhesive contributes to the suppression of resonances in the hearing-critical mid-frequency region. To achieve optimal low frequency stiffness, a two-point mounting is used to connect opposite panels without spreading resonance to other parts of the cabinet. The result is a “silent” body without noticeable peaks, which is the cornerstone of the Castle brand philosophy.

Both models of the Windsor series use a 4th order LKR (Linkwitz-Riley) crossover which provides the best integration of the dynamic drivers. All critical inductors in the crossover are air-core.

Castle is known for its craftsmanship in natural wood veneer cabinets and the new Windsor series is no exception. Their cabinets can be finished with high-quality walnut or mahogany veneer from sustainable woods. Each pair of speakers is hand-finished in tone-on-tone mirror veneer and waxed. Finishing each column takes several days.


As is the case with most British audio brands, Castle speaker production moved to East Asia some twenty years ago to keep retail prices at the level required by the market, while development remained in the UK.

Last year, IAG, which owns the Castle brand, introduced a new Made in the UK initiative., which will allow the production of certain products to return to the UK without a sharp increase in costs. IAG has expanded its manufacturing facilities at its base in Huntingdon, Cambridgeshire to include core manufacturing, assembly and finishing processes for specially selected products, in addition to the R&D department already located there.

A 9,000 sq.m. production facility has been added to the existing building. feet, equipped with a new anechoic chamber, for a total of 25,000 sq. feet of office, laboratory and manufacturing space. The Windsor Earl and Windsor Duke are the most recent models to benefit from new equipment, following completely redesigned versions of classic acoustic models from the group’s sister brands Castle, Mission and Wharfedale, for example,Wharfedale Dovedale .

The Castle Windsor Earl and Windsor Duke speakers will go on sale in April 2023. In the UK, the suggested retail price is £3,850 and £4,500 for a pair of speakers in natural walnut or mahogany veneer respectively. Signature open-frame speaker stands are available as an option, adding £400 to the entry-level Windsor Earl and £500 to the Windsor Duke .


The main technical characteristics of Castle Windsor Earl acoustics:

  • Type: passive two-way bookshelf speakers
  • Acoustic design: phase inverter, port on the back of the case
  • Tweeter: Microfibre soft dome driver
  • Mid/Woofer: 165mm woven polypropylene cone
  • Crossover frequency : 2.2 kHz
  • Sensitivity: 89 dB (2.8 V at 1 m)
  • Rated impedance: 8 ohm
  • Minimum resistance: 4.3 ohm
  • Recommended amplifier power: 25 – 100 W
  • Frequency response: 58Hz – 22kHz (+/-3dB)
  • Lower limit of the operating range: 45 Hz (-6 dB)
  • Case Volume: 15.8 L
  • Single column dimensions (H x W x D): 430 x 240 x 260 mm

The main technical characteristics of acoustics Castle Windsor Duke:

  • Type: passive two-way bookshelf speakers
  • Acoustic design: phase inverter, port on the back of the case
  • Tweeter: Microfibre soft dome driver
  • Midrange/woofer: 200mm woven polypropylene cone
  • Crossover frequency : 2.1 kHz
  • Sensitivity: 90 dB (2.8 V at 1 m)
  • Rated impedance: 8 ohm
  • Minimum resistance: 4.2 ohm
  • Recommended amplifier power: 30 – 150 W
  • Frequency response: 52Hz – 22kHz (+/-3dB)
  • Lower limit of the operating range: 39 Hz (-6 dB)
  • Case volume: 26 l
  • Single column dimensions (H x W x D): 470 x 280 x 310 mm