Floorstanding loudspeakers — Estelon X DIAMOND

The X Diamond is a three-way model in the X Series of floorstanding speakers made by Estelon, the company Alfred Vassilkov founded in Estonia in 2010. It pairs Accuton ceramic cones with an Accuton diamond tweeter in a sculpted cabinet moulded from a marble-based composite, a shape that defines the brand's look. The current version of the model is the X Diamond Mk II.

Key specs that matter

Estelon fits a 280 mm Accuton ceramic sandwich woofer, a 173 mm Accuton ceramic mid-woofer and a 25 mm Accuton diamond inverted-dome tweeter. Frequency response runs from 22 Hz to 60 kHz, sensitivity is 88 dB at 2.83 V and nominal impedance is 6 ohms, falling to a minimum of 3.8 ohms at 55 Hz. Power handling is rated at 200 W, and Estelon gives 20 W as the lowest usable amplifier power. The tower stands 1370 mm high, 450 mm wide and 640 mm deep and weighs 86 kg. Estelon specifies it for rooms of 25 to 80 m2.

Engineering and use context

Diamond pairs very high stiffness with very low moving mass, so the tweeter's lowest break-up mode sits far above the audible band and its output reaches 60 kHz. With an inverted dome the voice coil sits close to the plane of the baffle, which helps bring the tweeter into time alignment with the cones. The large woofer uses a ceramic sandwich to keep its wide cone stiff, while the mid-woofer has a solid ceramic membrane. Bass is reflex loaded. The marble-based composite of the enclosure is dense enough to damp panel resonances, and its curved walls avoid the parallel surfaces that support standing waves. The cabinet narrows towards the top, so the tweeter sits in a small section with little diffraction, and the base holds the woofer. Estelon designs its own crossover and wires it with Kubala-Sosna conductors. The filter splits the range at 75 Hz (third order) and 2 kHz (second order), while the Mk II network uses Mundorf Supreme resistors and SilverGold oil film capacitors. Standard finishes are Black Lava Liquid Gloss and White Gloss, custom paint can be ordered, and Estelon covers the speaker with a five-year warranty.

Pairing

Since the lowest impedance point lies in the bass region, where most energy is, the X Diamond is best matched with solid-state amplifiers of 100 W or more that stay stable into low impedance. Current delivery matters here more than the rated power figure.

Alternatives

The Estelon XA is the earlier X Series floorstander that introduced the company's design language.