The brand was formed with the founding concept of being a complete loudspeaker manufacturer and despite changing times and the globalisation of manufacturing, Castle maintains the same principle as the basis for the company.
Most of the bass units in our range feature cones made from woven carbon fibre, a light yet exceptionally stiff material with good internal damping. Our voice coil formers have exceptional power handling ability, while we also use innovative magnet assemblies with the highest quality copper and aluminium wire.
This means a far more linear motion is maintained, improving accuracy and dynamics, while reducing distortion, the latter results in a reduction of the moving mass of the driver, a vital parameter in producing speakers capable of maximising the impact of modern source components and program material.
We have also designed our tweeters to match the sonic performance of our bass units and so to enhance all musical accuracy of all Castle loudspeakers. They offer extended and substantially flat response characteristics with very low distortion and are married with bass units through crossovers built with the highest quality components.
Veneer sections are glued to individual panels and then held under high pressure in purpose-built clamps for the glue to dry naturally over 48 hours. On completion, each cabinet is hand-sanded and varnished to perfection, with the quality and consistency of the finish checked every step of the way.
Each leaf of the veneer is selected by eye to suit the size of the cabinet and each pair of the cabinet is manufactured in mirror-image-matched pairs, even the black ash ones. Castle selects the finest crown cut quality veneers from around the world and whenever possible, from properly managed forest resources.
Our engineers work hard to develop unique acoustic properties of the cabinets as well as the drivers themselves. In-house manufacture gives us the major advantage of being able to develop cabinets and drivers in tandem, and carry out fundamental research into the interactions between the drivers, crossovers and the cabinet. Our integrated design approach gives us the further benefit that systems can avoid complex crossovers. It is widely understood that fewer, high quality components in a simple crossover network give a cleaner sound.
Here we can see an illustration of a Castle Knight speaker, which utilises a unique approach to transmission-line loudspeaker design. Using twin pipe technology and using the cabinets internal volume, bass response is extended diminishing the need to use unruly reflex ports.
In most loudspeaker designs room modes are easily excited by forward or rear facing ports, resulting in a ‘boomy’ sound. This twin pipe system instead couples the bass response within the cabinet enclosure using a twin-pipe quarter wave design for a smooth and even bass response.