The Grand Seiko Hi-Beat SLGH005 “White Birch”

The presentation in early 2020 of the Grand Seiko “White Birch” or “Shirakaba” already gave us a great impression and it clearly was one of the watches I was eager to see in the metal. There’s no turning around, this SLGH005 represents the best of what GS can do for its permanent, classic collection. Mechanical noblesse, slightly renewed design language merged with respect of the brand’s traditions, exquisite finishing and a dial that is out of this world. And having this piece with us at the office for a review only confirmed what we imagined. So let’s have a closer look at this new Grand Seiko Hi-Beat SLGH005 White Birch.

Background

This SLGH005 is a new reference in the brand’s collection but isn’t entirely a novelty. It is built on existing foundations, which were introduced in the context of Grand Seiko’s 60th-anniversary, celebrated back in March 2020. What this SLGH005 is the first model in the permanent collection to be equipped with both a new design language and, most importantly, the brand’s new automatic movement, featuring an innovative escapement, the Hi-Beat Calibre 9SA5. In tune with the jubilee celebrations, Grand Seiko indeed presented this new movement, inside a limited edition gold watch, the reference SLGH002 – the starting point here, as we’re basically talking about identical watches here, with just different materials and colours.

Then, still part of the 60th-anniversary collection, Grand Seiko unveiled a stainless steel limited edition with a blue dial, the reference SLGH003. Now with the SLGH005 White Birch, both the case’s design and this movement are appearing in the brand’s catalogue in non-limited production. And, in addition, there’s this new dial… and what a dial it is.

The new Grand Seiko Hi-Beat SLGH005

Whatever the fact that the White Birch is a mix of already existing elements, it remains one great surprise. Creating an innovative movement and offering it in limited edition models is a thing. Producing it on a larger scale and being confident enough in its reliability and precision is another. So, in addition to launching a new model with the SLGH005, Grand Seiko is also sending the message that the Calibre 9SA5 and its Dual Impulse Escapement are here to stay and they do indeed perform in the real world. Innovation for the sake of innovation is not something you’ll see at Grand Seiko.

So let’s start deciphering this new Grand Seiko Hi-Beat SLGH005. There’s a lot to say, simply because there’s a lot going on with this watch. There’s no forgettable parts, no side of this watch that would simply let you say, “ok, let’s move to something else” and look at another detail. Case, dial, hands and indexes, crystal, movement, and even the bracelet have stories to tell. That could have come at the risk of being overdone, though, but it’s not. One important thing with this SLGH005 is also about its consistency and coherence.

Let’s start with the case. First of all, the good news comes from the proportions. 40mm in diameter, 11.7mm in height, 47mm lug-to-lug. Classic dimensions for an all-rounder watch, in line or even slightly smaller than competitors such as the Rolex Datejust 41. Also, due to a pleasantly curved profile, a thin caseband (with some of the height absorbed by the crystal and the caseback) and a nice integration of the bracelet, the watch sits very comfortably on the wrist and feels balanced. It “hugs” the wrist nicely and will be a great daily companion.

Design-wise, there’s no doubt regarding the provenance. The SLGH005 White Birch is, undeniably, part of Grand Seiko’s design codes. However, just like the SLGH002 that introduced this case, it feels modernized, slightly different and, mostly, extremely well executed. Already in the past years, Grand Seiko watches always felt impressively manufactured and this new generation only increases this feeling. The level of precision and details, in this price range (but even in higher ranges), is simply stunning. The dividing lines between brushed and polished surfaces are perfectly clean and the finishing themselves are flawless.

Specifically, the Zaratsu (distortion-free) polished surfaces never cease to amaze me. Some details are very refined, like the bezel for instance, with its vertically brushed top surface and polished sides. In the same vein, a small polished inner chamfer sits inside the lugs, animating the case and also adding a sense of luxury. There’s finally a very pleasant shine to this watch, but not in an ostentatious way. The watch is topped by a nice box-shaped sapphire crystal, adding a warmer touch, and is 100m water-resistant, which is always pleasant. It even features lug holes, in case you want to remove the bracelet.

But it is time to talk about the big deal with the SLGH005, its white birch-inspired (or Shirakaba if you want to play it Japanese all the way). It is well known now that Grand Seiko masters textured dials, something that really started to become famous with the Snowflake watch. For this model, the brand once again takes inspiration from the environment that surrounds its manufacture, the dial being a reference to the forests that thrive in northern parts of Japan and that grow in profusion near the Grand Seiko Studio Shizukuishi where this watch is made.

First of all, to my surprise, the dial isn’t silvery-white as I expected it to be, based on the press images. It has an intense metallic, silver colour with a shimmering effect. Nothing bad with this, as it actually creates a coherent feeling with the metal case and bracelet combination. It just that I was expecting something more matte, more white-ish. The texture itself is impressive, extremely detailed when looked closely and, thankfully, less blatant when worn on the wrist and seen from a distance. From about a meter, it becomes less obvious. I’m sure this pronounced and non-linear texture won’t be to everyone’s taste, yet it really needs to be seen in the metal and experienced live to capture its true beauty. There’s a certain poetry in this dial, a cold, slightly dramatic feeling that attracts your eye…

The rest of the dial is typical Grand Seiko, and impresses as much as the textured base. Once again, the hands and indexes are some of the best-executed you’ll find on the market, at least as produced by a mainstream brand. You can search… No one does hands and markers with the same level of precision in the sub-10k range. Ultra-sharp, with near-perfect polished bevels, the hands and makers of the SLGH005 are also slightly different from the previous models created by GS. They are bolder, less slender and their shape is also more complex.

A good point, despite the full silver colour of the dial, the indications remain well separated from the base and legibility is great in all daytime conditions. The mirror-polished surfaces of the hands, as well as the recessed areas on the markers, help a lot, since they move from bright white to almost black reflections, thus being well separated from the base. At night, legibility is poor since this watch doesn’t come with luminous material. The only thing to break this monochromatic silvery look is the seconds hand, executed in blued steel, running smoothly over the dial. Sorry to say it again, but this dial is absolutely stunning.

The Grand Seiko Hi-Beat SLGH005 comes equipped as standard with a stainless steel bracelet, with flat surfaces brushed and polished sides. Regarding the execution of the bracelet, no debate, it’s solid, precisely manufactured, equally well detailed as the case. It is closed by a folding clasp with safety push buttons and its length can be adjusted by screws (and not those horrible pins you find on more accessible watches). Maybe a fine adjustment clasp would be a nice addition, but overall, there’s really nothing to complain about the bracelet. Except, and that is my concern, the fact that it is both wide – at 22mm – for a watch of that diameter, and a bit bland. A few polished accents might have been welcome in this context. Honestly, I think I’d wear the SLGH005 on a nice taupe-coloured leather strap, or a blue calfskin strap with silver stitchings… But at least, I’d be happy to have a steel option for hotter days.

The Hi-Beat Calibre 9SA5

The SLGH005 White Birch isn’t just a pretty face. It is also a watch with serious watchmaking credentials. It indeed comes with Grand Seiko’s innovative escapement, the Dual Impulse. In an industry where the Swiss lever escapement represents approximately 99% of the production (and that for more than 250 years), and where only one other exotic escapement is produced on an industrial scale, GS’ development is more than noticeable.

Reminder about the escapement

The basic operating principle is the following: energy is stored by the mainspring inside the barrel. The energy is released via the gear train that drives the hands. The speed at which the gears rotate is controlled by the regulator that comprises the escapement and the oscillator. The escapement transfers energy to the oscillator (the balance wheel and its coiled hairspring) via impulses. In return, the oscillator regulates the escapement. Its oscillations unlock the escapement at a regular rate allowing the gears to rotate and the mainspring to unwind progressively.

The role of the escapement, composed of an escape wheel, a pallet and a roller, is to transfer the rotary motion of the escape wheel into a back and forth lateral motion of the pallet, giving an impulse to the balance wheel. The pallet fork locks and unlocks with the escape wheel at each vibration of the balance wheel. The escapement controls the release of power from the mainspring, which in return is regulated by the pendular motion of the balance/hairspring couple. In short, the escapement is involved in both the chronometry and the kinetic chain.

Now that we’ve covered the basics, what is Grand Seiko’s Dual Impulse Escapement all about? In addition to the use of modern material and production technologies, as well as high-frequency (a classic for the brand), what really matters in this movement is the geometry of the escapement, its architecture and the way the locking and impulse phases are executed.

First of all, the architecture and shape of the parts used for this new Dual Impulse Escapement are different from what’s in use in the classic lever escapement. As you can see, the escape wheel has a star shape with 8 arms, instead of a wheel with teeth. This new escape wheel is openworked, just like the pallet fork, to make the parts lighter and thus more energy efficient. These two parts have been crafted thanks to micro-electromechanical system technology (MEMS), allowing them to be machined to tolerances of one-millionth of a gram and to be 5% lighter than others, meaning less power is required to actuate them. The main concept behind this Grand Seiko Dual Impulse Escapement is that the locking and impulse functions are dissociated – a solution similar to the Audemars Piguet or the Omega Co-Axial escapements, for example. In one direction, power is transmitted directly to the balance (clockwise), as the roller receives impulse directly on its jewel. In the other direction, it receives an indirect impulse via the pallet fork, as in a traditional escapement. Thanks to this dissociation of the locking and impulse functions, with friction occurring in only one direction, the escapement is more efficient (less friction means less energy required) and more wear-resistant.

This new Dual Escapement works in conjunction with a new free-sprung balance that is more resistant to shock and friction and retains its precision for longer periods. And while most Grand Seiko movements rely on a flat hairspring, this new movement has an overcoil – to achieve the optimal shape for the overcoil, more than 80,000 simulations were undertaken in the lab. All of this to achieve greater efficiency and chronometry, better energy consumption and greater stability in the long run.

To house this new mechanical development, Grand Seiko has created an entirely new movement, the calibre 9SA5. While there was nothing wrong with the previous movements made by the brand, this new engine marks a step up in horology, being slimmer and far more handsome than before. Measuring 5.18mm in height, this brand new movement is 15% slimmer than the current 9S Grand Seiko high-beat calibre. This was achieved with an innovative horizontal layout of the barrel and gear trains. The two barrels are arranged in sequence to extend the power reserve from 55 to 80 hours. Another improvement, the balance is held in place by a transversal bridge, which ensures greater stability and shock resistance. Finally, this watch runs at a 5Hz (or 36,000vph) frequency, which is another step in the path for accuracy. Indeed, this movement is rated for +5 to -3 seconds per day.

Another important thing to note about the Calibre 9SA5 is its decoration and design. While previous GS movements were cold and technical looking, this new engine is warmer and has more… Swissness, or at least more charm, more decorum, more warmth to its look and feel. The bridges are nicely curved with polished bevels on the edges and more subtle wave patterns on the flat surfaces. The oscillating weight comes with a new, lighter and more opened design, allowing for a better view on the very nicely decorated movement. Altogether, this movement is more theatrical, more demonstrative than previous 9S engines.

Thoughts

I have to say that, with the exception of the bracelet, which has nothing wrong but mostly is less demonstrative than the rest of the watch, I’m truly stunned by this new Grand Seiko Hi-Beat SLGH005 White Birch. The execution is impeccable on all levels and the proportions are great for a daily-wear, sporty-chic watch. The cold, slightly melancholic look of the dial is extremely attractive and its execution, whether the base or the elements of the display are, as you’d expect from GS, exquisite. Finally, the movement is visually, horologically and mechanically impressive.

And when you look at this SLGH005 in details and then compare this with its sticker price, you end up with a watch that offers a lot for the money. It isn’t a cheap watch, for sure, and thus compete directly with Swiss heavyweights – but it does truly have the weapons to compete. Considering what you’ll get in return, I’d say that price is more than fair.

Availability & price

The Grand Seiko Hi-Beat SLGH005 White Birch has been launched in the brand’s permanent collection and is now available from GS boutiques, GS online shops and authorized retailers. It is priced at EUR 9,500 (incl. taxes) or USD 9,100 (excl. taxes).

For more details, please visit www.grand-seiko.com.