What are the differences between the Grand Seiko SLGA009 and SLGH005 “White Birch” watches?

Grand Seiko is wasting no time in 2022, dropping two new icy blue US Special Editions straight out of the gate and now making waves with a second “White Birch” inspired watch: The Grand Seiko SLGA009. This release ushers in a new era for Grand Seiko watchmaking that the brand refers to as Evolution 9 – a rebranding of what we formerly knew as Series 9 design.

Combing through feedback and reactions on social media, it is clear that the overwhelming majority of enthusiasts and buyers are impressed with the watch. But there is also an air of confusion as well, with some wondering what is actually new about the release and the strategy of delivering what seems like another version of the exact same watch (the Grand Seiko SLGH005). When you dig deeper, however, aside from the main difference of their calibers, there are many subtle differences that I’ll run through in greater detail below.

Case thickness and caseband

Admittedly, much of the external design and finishing of the SLGA009 is the same as the original SLGH005. The only minor highlights of difference, in this regard, are that the SLGA009 is .1mm thicker than the SLGH005 at 11.8mm thick, and that there is a greater presence of a polished surface where the bracelet meets flush to the case. For a more in-depth explanation of the Evolution 9 case form inspired by their 44GS geometry, you can check out our SLGH005 introduction here. Now onto more points of difference…

The studio where the new watch is made

Grand Seiko timepieces are manufactured by multiple studios, each in their own location with their own specialties. The Grand Seiko Studio Shizukuishi, pictured above, handles 9SA5 Hi-Beat powered references like the original SLGH005 “White Birch”. Grand Seiko Studio Shinshu, on the other hand, is the studio where all watches powered by Spring Drive are made and is therefore the studio that produces the new Grand Seiko SLGA009 “White Birch”. While they are each in-house studios that work under the Grand Seiko name, subtle differences in approach seep into the timepieces they each fabricate.

Spring Drive versus Hi-Beat

The clearest difference between the new Grand Seiko SLGA009 and the previous SLGH005, as disclosed by the dial text at 6′ on each dial and their exhibition casebacks, are the calibers powering each watch.

The SLGA009 is powered by the recently developed Spring Drive 9RA2 caliber. As a Spring Drive caliber it offers incredible precision, pledged to run at a rate of ±0.5 seconds per day. The movement is equipped with an “Offset Magic Lever” winding system that reduces its thickness, allowing the SLGA009 to clock in at 11.8mm instead of the 12mm or more typically found on 9R65 Spring Drive powered models. Its two barrels provide up to 120 hours of power reserve, totalling five days – a two day or 48 hour improvement over the 9R65. Its bridge lines and edges, as well as the edges of the screw holes, are diamond-cut to reflect a very high quality finish that collectors will appreciate. The bridge and openworked rotor feature a clean frosted finish, reflecting a more modern aesthetic befitting modern Spring Drive technology. Saving the largest draw (for some) for last, the power reserve indicator is placed on the movement bridge instead of the dial – addressing the familiar complaint that the dial-side power reserve indicators interrupted the aesthetic of previous Spring Drive dials.

Its predecessor, the SLGH005, was the first standard production model to utilise the revolutionary 9SA5 Hi-Beat caliber. Notable features include an entirely new dual-impulse escapement designed in-house, twin barrels with 80 hours of power reserve, a hi-beat frequency of 36,000 vph, a new free-sprung balance, full balance bridge, and new Grand Seiko overcoil hairspring distinct to the brand and perfected through over 80,000 simulations. Like the 9RA2, the bridges are exquisitely bevelled and diamond cut, but it boasts more traditional striping as well.

Dial texture and inner-bezel

While both dials clearly live up to the “White Birch” muse, the execution is not as identical as it may seem at first glance. The real difference is their textures. Grand Seiko explains: “Unlike the deep waves of the SLGH005 dial, the texture [on the SLGA009] is more subtle and delicate.” In my opinion, the new texture found on the SLGA009 is more refined and the pattern more structured. The SLGH005, by comparison, feels a bit more rustic. The depth of the texture carving also inevitably changes how the dials each reflect and play with light.

Unless you look very closely, you also might miss the fact that the stepped inner bezels have ever so slightly different widths, the original SLGH005 appearing to be more narrow. On the stepped inner bezel of the SLGH005, you’ll find minute hashes that kiss the top and bottom and boxed hour markers with a more squared appearance. Pivot to the SLGA009, you’ll notice a slight gap between the top of the stepped inner bezel and where the printing begins for the minute and hour markers. With the added height, it also appears that the bolded hashes indicating the hours and fifth minutes are taller and more rectangular in favour of squared or boxed. With the slight difference in size between the two stepped inner bezels, it also appears that the flat textured part of the dial is negligibly smaller on the SLGA009 than the SLGH005.

Capped seconds hand versus no cap

In regards to the hands, the central hours and minutes hands take the same format on each model albeit being (possibly) minutely different in width and length on each. The clearest difference, in regard to the hands, is the central seconds hand. Yes, both are blued, and no I am not referring to how they sweep across the dial differently. On the SLGA009, the central seconds hand is capped – interrupting the blued nature of the central second hand. When you look at the SLGH005, there is no cap where the hands are set onto the dial and therefore the hand is blue throughout. While there may have been technical incentives for the difference, likely due to the rotation of a fluid hand (Spring Drive) versus a more stepped or ticking hand (Hi-Beat), for the wearer it is merely an aesthetic variance.

Date window sizing and aesthetic.

I won’t labour this point, because once it is pointed out it is pretty clear to see and doesn’t really change much in terms of appreciating each dial. The SLGA009, due to its 9RA2 Spring Drive Caliber, boasts a larger and wider date window with a date wheel that has a wider font for the black numerals on the white disc. Conversely, the SLGH005 dials has a smaller squared date window – in turn having a more narrow font to the black date wheel numerals on its white disc. Where dial purists may really find a major difference is the presence of a small hash to the right of the date window on the SLGH005. It was not really a heated point of discussion upon its release, but it stands out a bit more now that we see a “White Birch” dial without it on the SLGA009. It was probably removed to accommodate the wider date window, but it also removes what now seems like a bit of dial zit by comparison – a small but impactful refinement on the succeeding SLGA009 model.

Crown size

Both stainless-steel watches are 100 metres water-resistant with screw-down crowns. That being said, the crown is a tad wider (or taller) on the Grand Seiko SLGA009 5 Day Spring Drive then the 9SA5 Hi-Beat SLGH005. For some this may be “cool beans” or a “who cares” point of differentiation. But hey, I am just being thorough here…

Editor’s Note: This article has been amended to reflect the price correction issued by Grand Seiko on 13/1/2022, both watches are in fact priced at $9,100 USD