Wharfedale Diamond 12.1 Bookshelf Speaker

Klarity affords focus
NEW Klarity™ cone material, formulated from a blend of Polypropylene and mica adds stiffness to reduce flexing, enabling a lightweight cone with high rigidity, low colouration and lightning-fast response.

Low colour and expression
The Klarity™ cone is fitted with a low-damping surround, thereby achieving both low colouration and expressive dynamics. By simulating many different cone shapes and adding ribs to provide further stiffening, a flat response curve was achieved without resorting to a high-damping surround, thereby striking the ideal balance.

A magnet of forces
A precision-made magnet system with an aluminium compensation ring to minimise the effect of variations in inductance as the voice coil travels. This contributes to an absence of distortion and intermodulation generated by the ‘motor system’.

A voice coil beyond this class
The voice coil is wound on a high-power epoxy/glass fibre bobbin highly unusual in speakers at this price level. This has the advantage of not adding eddy currents and delivering greater power handling than an aluminium bobbin, whilst also being much stiffer than the Kapton type associated with this price-class.

DIAMOND highs
The 25mm dome is made from a woven polyester film with a high-loss coating to deliver open and smoothly extended high frequencies. The magnet system and the front plate have been optimised for wide dispersion and uncompressed behaviour. The front plate is flat and exposes the dome as much as possible; only a very short duct on the front plate balances the acoustic load and improves the SPL (sound pressure level) measurement.

A crossover of style
The crossover network uses an acoustic LKR 24dB topology. This includes air-core inductors of the type more commonly found in high-end speakers, selected because they produce the lowest distortion of all inductor types. As the resistance of the coil is higher than a standard laminated steel or ferrite core inductor, the magnetic structure of the mid/bass driver has been modified to compensate, resulting in fast, clean bass with no distortion from the inductor.

Firm and fair
The DIAMOND 12.1 ’s rear-ported enclosure is precisely sized so that the internal volume works in harmony with the drive unit system to deliver the desired sonic result. A multi-layered sandwich design subdues the identifiable characteristics of the cabinet’s ‘sound’. Even the resonant properties of the glue between the layers was measured to determine the optimum combination.

Brace yourself
Inside the cabinet, Intelligent Spot Bracing connects opposite walls with a specific form of the wood brace to achieve an optimal reduction of cabinet resonance. These braces are precisely modelled by computer simulation to improve upon the commonplace ‘figure of eight’ brace, which may simply transfer resonance from one wall to another.