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Koetsu Blue Onyx

Koetsu Blue Onyx

In an age of hype, where everyone ceaselessly self-promotes to gain attention and market share, Koetsu represents an oasis of calm. Founder Yosiaki Sugano (1907 – 2002) was a man of many parts – artist, musician, swordsman, calligrapher, business executive, and father. He drew inspiration from the 17th century Japanese artist Honami Koetsu (1558-1637).

So what else but to adopt the name of his hero Koetsu when deciding to manufacture high quality MC pickup cartridges back in the late 1970s? Amazingly, the company seems never to have advertised its products, nor produced any sales leaflets. All the same, word quickly spread among audiophiles, and the Koetsu legend was born. In 2014 Koetsu still doesn’t have an official website. Twitter? Facebook? What’s that?

With Koetsu, Hearing was Believing. Once you’d experienced a Koetsu, little-else sufficed. The original models were quite large, with a rosewood body covering. Later models slimmed down a little, and featured exotic body materials, from lacquered Urushi finishes, to the use of natural gemstones including Jade and Onyx.

Sugano’s minimalist approach soon earned him mythical status in hi-fi circles. It’s said his ‘death’ was erroneously reported no less than three times – something that apparently pleased him no end! It all became part of the Sugano legend, adding to the mystique of this most unusual of brands. Finally, though, reports of his death were not greatly exaggerated, and the legend died just a couple of months short of his 95th birthday. However, the Koetsu name lives on through Sugano’s son, Fumihiko, who was trained to take over his father’s legacy, and keeps the brand clouded in mystique to this day.

Koetsu cartridges still enjoy near-mystical status; the creations of  a quiet infinitely-patient sage, steeped in ancient wisdom, slowly and painstakingly crafting transcendental products  – and all this passed down the line from father to son, master to new master. Inevitably, the legend is somewhat at odds with the reality. But still the myth lingers on, and with good reason.


There is a magical quality to the sound of a Koetsu – something beyond measurement and statistics. Naturally, precision engineering and using only the best materials have long been an essential part of the mix. But the end result exceeds the sum of the parts. Call it art; call it alchemy; call it BS – for those with ears, a Koetsu was (and is) special.

The Koetsu experience comes at different price points – from (relatively) affordable to ‘is that a misprint?’  Even the basic models sound excellent, but as you move up the range, the sound grows increasingly rarefied. Many Koetsu pickups feature 99.9999 purity copper wire for their coil windings with a special silver cladding that consists of a silver sheath slowly drawn over the copper conductor, but the Blue Onyx is said to be Platinum Coiled. As ever, details are sketchy – so we presume the copper is Platinum sheathed. The motor assembly employs Samarium Cobalt magnets for their concentrated power.

The cantilever is made from boron, but perfectionists with even deeper pockets can go for an optional one-piece diamond cantilever and tip. This avoids the interface between stylus tip and cantilever, and increases rigidity, albeit for an extra £3,666. People say you can’t put a price on perfection; actually, perfection costs precisely £11,066!

The body shell is fashioned from powder blue Onyx, so each cartridge has a uniquely beautiful appearance – like a piece of exotic jewellery. It’s not a small cartridge, incidentally – 23mm long and 14mm deep – and also quite heavy at 14.8g. Your chosen tonearm will benefit from a heavy counter weight. Optimum playing weight falls between 1.8g to 2g. 1.8g offers slightly greater transparency and fine detail, but 2g reduces surface ticks and improves tracking slightly. Now, we’re always told not to trust our ‘first impressions’ when evaluating hi-fi. But calm rational objectivity can be difficult once something like the Koetsu Blue Onyx begins to play…

The Blue Onyx sounds impressively sharp, yet at the same time, beautifully refined with an effortless velvety smoothness that’s almost uncanny. It’s every bit as detailed and dynamic as you could wish for, yet wonderfully poised and relaxed-sounding. In musical terms, the presentation is effortless and natural. The music seems to ‘happen’ between your loudspeakers; voices and instruments materialise before your very ears.

The timbre is somehow both mellow and sharply focused – smooth and subtly shaded, yet crisp and tactile. It’s a beguiling mix of opposites; sonorous warmth and silky smoothness, hand in glove with immediacy and crisp attack. Dynamically, the Blue Onyx ‘projects’ with an impressive sense of power. The sound is very energetic and colourful, yet unexaggerated and truthful too.

With a full and solid bottom end, liquid midband, and brilliant translucent highs, there’s much to ravish the ear. Transient detail is pin-point sharp, yet without aggressiveness, and always wonderfully homogenous. This ability to produce vivid, sharply-focussed detail without sounding ‘hard’ or over-driven is very much a Koetsu trademark.

I found the Blue Onyx musically engaging and positive-sounding, while remaining relaxed and refined. This mix of opposites is apparent on most sorts of music, particularly human voice. Whether it’s an unaccompanied solo singer, massed choral forces, or the lead vocals in a rock or pop track, the Blue Onyx delivers natural believable results.


Clarity is quite stunning. The way this cartridge separates individual vocal lines, and allows subtle instrumental passages to be heard, borders on the miraculous. It’s also good at recreating a sense of aural space – revealing the natural hall ambience behind individual voices or instruments.  As a result, each retains more of its identity.

Yet, for all its vividness, the Blue Onyx is surprisingly easy to listen to. It delivers a very coherent sound. Opposing contrasts – high and low, loud and soft, sharp and smooth – co-exist in perfect balance. So the end result is harmonious and cohesive, and the music unfolds in a way that gives you more time to listen – more time to unravel the individual strands that form part of the whole.

It’s the polar opposite of a sound that is aggressive and ‘forward’ – bombarding the ear with a welter of unrelated leading edges so the brain struggles to make sense of it all. The Blue Onyx is delightfully easy to listen to. It delivers a very ‘ear-friendly’ sound. Your brain has less processing to do, so it’s better able to take in the entire musical scene, and make better sense of the whole.

But please understand – the refinement of the Blue Onyx is something innate; not something false that’s grafted on to each recording regardless. It’s very much a pickup that faithfully reflects the individual qualities of each recording – an open transparent window on the music. It will sound sweet and beguiling one moment, then tack-sharp and crisp the next – often during the same track.

Clearly, the Blue Onyx is one magnificent cartridge. It’s among the finest you could ever hope to hear, with few peers when it comes to turning those squiggly grooves into living breathing music. You’ll listen to it with rapt attention – much as you’d listen to real musicians playing live in front of you. Each Blue Onyx is made to order, so there may be a long delay before you get one. But, don’t let that put you off; the wait will be worth it!


Price: Koetsu Blue Onyx moving coil cartridge (boron cantilever) £7,400.

Diamond Cantilever Version £3,666

Distributed by: Absolute Sounds

URL: www.absolutesounds.com

Tel: +44(0)20 8971 3909

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