The Wharfedale Diamond 12.0 is the smallest bookshelf speaker in the ’12 Series’ range and is suited to small to medium size rooms where the visual impact is kept to a minimum but the sound is still great, albeit on a smaller scale. With the dramatic clean-sheet redesign of the Diamond 12 range, spearheaded by world-renowned speaker designer Karl-Heinz Fink, Wharfedale have once again raised the bar for what affordable audiophile quality speakers can achieve. At the price these exciting Wharfedale Diamond 12.0 compact bookshelf speakers are hard to beat.
The Wharfedale Diamond 12.0 might just be the sleeper in the range. It is by far the most compact model and that really appeals to some people where space is at a premium or the speakers need to be as inconspicuous as possible. The Diamond 12.0 employs a smooth sounding 25mm (1″) textile dome tweeter and an advanced 100mm (4″) mid/ bass driver constructed of a new material called Klarity which combines traditional polypropylene with mica for added strength and a level of clarity and energy which is truly refreshing.
Developed in Cambridgeshire, England since 1982, Wharfedale’s famous Diamond speakers have served as the classic entry point to true high-fidelity sound, their exceptional sonic value for money earning numerous ‘product of the year’ accolades in the UK and around the world. With the introduction of the all-new Diamond 12 Series, Wharfedale once again raises the bar for affordable, high-performance loudspeakers.
New Klarity Driver
The Difference Is Clear: Since the Diamond 8 Series in 2001, Wharfedale has made the mid/bass cones for every Diamond generation from Kevlar. 19 years and many award-wining ranges later, Wharfedale has developed a new composite called Klarity. The chief ingredient of Klarity is polypropylene, a material that has been used to make speaker cones since the BBC researched its use for this purpose in the 1970s. Polypropylene cones are renowned for their characteristically low distortion and controlled ‘breakup’, as well as their resistance to moisture in the air. They also have a reputation in some quarters for sounding a little ‘unexciting’ – a perception that is largely the result of mediocre engineering. When designed and implemented optimally, polypropylene cones can sound enthralling.
The Secret Revealed
To make Klarity, Wharfedale adds mica to the formulation. This increases stiffness compared to polypropylene alone, reducing flexing and enabling a lightweight cone with high rigidity, low colouration and lightning-fast response – ideal characteristics to deliver both accuracy and excitement.
Attention To Detail: Polypropylene speaker cones are often combined with high-damping surrounds to achieve a smooth response curve. However, the hysteresis of these surrounds can restrict dynamics and make bass sound somewhat ‘soft’. For the Diamond 12 Series, the aim was to combine the Klarity cone with a low-damping surround, thereby achieving both low colouration and expressive dynamics. This was not a simple task but, 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.
The Klarity diaphragms are driven by a substantial, 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. 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.
Refined Tweeter & Crossover
The Diamond 12 Series’ treble unit sports a 25mm dome 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, with a short duct to balance the acoustic load and improve the SPL (sound pressure level) measurement.
The treble unit combines seamlessly with the mid/bass driver via a crossover network using 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.
Carefully Crafted Cabinet Construction
The cabinet is a critical part of any high-performance loudspeaker. At entry-level price points, corners are often cut to constrain cost, but this is a mistake; no matter how good the drive units, their performance will be wasted if the cabinet’s construction is suboptimal. For this reason, Diamond 12 Series speakers feature cabinets constructed with a level of sophistication usually reserved for much more expensive designs.
The rear-ported enclosure of each model is precisely sized so that the internal volume works in harmony with the drive unit system to deliver the desired sonic result. The cabinet walls are made from sections of wood fibreboard of varying thickness, constructed in such a way as to subdue the identifiable characteristics of the cabinet’s ‘sound’ and ensure the drivers’ output remains unsullied. The resonant properties of each element – even the glue – were considered to determine the ideal combination of materials and placement. Inside the cabinet, Intelligent Spot Bracing connects opposing walls with a specific form of wood brace to achieve optimal reduction of cabinet resonance. These braces are precisely modelled by computer simulation to improve upon the commonplace ‘figure of eight’ brace, which can have the effect of transferring resonance from one wall to another.