Grand Seiko SBGA413 Review – A Detailed Look at the “Shunbun”

I grew up in Southwest Virginia and experienced four well-defined seasons. Little did I realize back then that I underestimated the numerous subtle nuances of a revolution around the sun and the “nature of time” it could convey.

Fortunately, Japanese culture, particularly Grand Seiko, has taught me more. The Grand Seiko SBGA413 “Shunbun” (Spring Equinox)  is both part of the Heritage Collection “Four Seasons” line initially launched in the U.S. (now available worldwide) and a larger group of the brand’s models that honor the Japanese concept of 4 main seasons with 6 phases for a total of 24 sekki.  

Also nicknamed the “Cherry Blossom”, the SBGA413 is an excellent example of the superb aesthetics and veneration for artisanal craftsmanship (Takumi) for which the Grand Seiko is known. Like its more well-known “Snowflake” older sibling, the Shunbun dial is breathtaking and mesmerizing, designed to depict the light pink cherry blossoms (Sakura) that quickly flower and fall in the Japanese spring.

But there is so much more to this time-measuring masterpiece than its pretty face. Let’s take a closer look at this amazing watch and gain a greater appreciation for its wholeness and beauty, both inside and out.

History

First, a short history lesson. In 1881, Japanese watchmaker Kintarō Hattori opened his watch and jewelry shop in Tokyo and named his growing brand “Seiko” in 1924. By the late 1950s, Seiko’s affordable and accessible watches were becoming popular worldwide. 

In 1960, the company launched the Grand Seiko sub-brand to produce luxury timepieces that would compete with their Swiss counterparts in both refinement and accuracy. In 2017, Grand Seiko became an independent brand.

Per the Grand Seiko website, the SBGA413 Shunbun is “a modern re-interpretation of the celebrated 62GS from 1967.” The 62GS contained Grand Seiko’s first automatic movement and was renowned for its no-bezel case and open, easy-to-read dial, multiple facets and striking angular lines on both the case and lugs, and highly polished (Zaratsu) surfaces, features which are still present and even more pronounced in the contemporary version.

Building on the successful 2005 launch of the “Snowflake,” the company’s first watch featuring a textured, artistic dial, Grand Seiko introduced the Heritage Collection’s “Four Seasons” line in 2019 in the United States only. 

However, in 2022, the company made the “Spring” SBGA413 and its sibling references—“Winter” (SBGA415), “Summer” (SBGH271), and “Fall” (SBGH273)—available online and in Grand Seiko boutiques around the world.

Case

The SBGA413’s “family resemblance” to the case of its ancestor 62GS is obvious at first glance in shape, dimensions, and finishing—but not material.

The case diameter is 40mm with a case thickness of 12.8mm (which includes the prominent, dual-curved, boxed sapphire crystal), and a lug width of 21mm coupled with a lug-to-lug distance of  46.5mm. 

Together with the case’s no-bezel open face and angular but curving shape and conforming lugs, the Shunbun’s “sweet spot” case specs make for a “right-sized” watch for a wide range of wrists (more on that later under “On-Wrist Experience”).

However, the case material is not your grandfather’s 62GS stainless steel. The Shunbun is instead made of grade 5 titanium, which is renowned for its strength, extreme light weight, and high scratch resistance.

Add to that a matching titanium bracelet (covered further under “Bracelets and Straps”), and you get an extremely comfortable, 3.5-ounce featherweight all-day wearing experience that would make you forget you’re even wearing a watch were it not for the way you keep staring at its stunning dial and fine finishing touches.

Although titanium has a slightly darker tone than stainless steel, Grand Seiko’s use of mirrored Zaratsu distortion-free hand polishing combined with brushed satin finishing on the multi-sided case and lugs makes the spaceship-strength material light up like a gleaming Samurai sword flashing in sunlight. 

While the case’s throwback style and superb finishing lean “dress”, its stamped, screw-down crown and 100-meter water resistance lend enough of a “sport” vibe to make it a versatile and potentially everyday timepiece. And if you still want grandad’s stainless steel after all, it is available in both the “Summer” and “Fall” versions.

The dual-curved, box-domed sapphire crystal is paired with a sapphire display caseback that showcases the innovative and ornate Grand Seiko Spring Drive. And therein lies one of the few legitimate pickable nits about the Shunbun: a large, gold Grand Seiko lion seal partially obscures the watch’s beautifully finished movement. Meant to honor the medallion caseback of the original 62GS, it was well-intended but overdone. 

Perhaps a less prominent and more transparent seal would still celebrate the brand’s heritage without hiding the intricate beauty and high-flying tech of the Spring Drive.

Dial

The well-executed SBGA413 case essentially serves as an ornate but still subordinate “picture frame” to hold the true star of the show: the highly textured, glistening, pale pink yet multichromatic Shunbun dial. It is intended to evoke the impression of the cherry blossoms that bloom and quickly fall around the Spring Equinox in Japan. 

Often the blooms fall onto water, swirl, and start to float away (like time itself), and the Japanese have a term for this also: hana-Ikada, which means “flower rafts”.

That’s an ambitious aim, but with a mix of old-school craftsmanship and proprietary modern techniques, Grand Seiko hits the mark. The dial’s texture is 3-dimensional, mimicking the undulations of a petal floating on water that look to me like “puffy” pale pink clouds etched with fine lines resembling an artist’s brushstrokes on a canvas.

Pink, that is, until they turn something else, like silver, white, or a combination of the three. The dial doesn’t just “play with the light” when you observe it from different angles. It orchestrates multiple wavelengths like a conductor does the many pieces of a symphony. With the Shunbun, you never know exactly which combination of colors you’re going to see, and it’s possible you may not even see the same one twice.

The dial is further festooned with a brushed satin Dauphine hour and minute handset and applied indices accented with Zaratsu polished edges that glint like sunlight on a stream’s surface. A gold-colored applied “GS” logo near 12 o’clock adds even more dimensionality. The black, printed “Grand Seiko” stamp and encircling minute track add contrast and character to the rippling, variegated surface.

A smooth, highly polished seconds hand, powered by the Spring Drive movement, sweeps more smoothly than any automatic ever could, converting the dial into a kinetic sculpture. The 72-hour power reserve indicator sits between the center of the dial and the 7- 8 o’clock positions. There’s a framed date window at 3. Both complications provide practicality and a pleasing touch of imbalance and interest to the serene, mostly symmetrical scene.

Like a masterpiece painting in a museum, no prose, poetry, or one-dimensional, high-resolution macro shot will ever do the Shunbun dial complete justice. You simply have to get hands-on and see it in person and from varying distances and angles to experience its full mesmerizing and transforming effect.

Movement

While the stunning “Spring” dial catches the eye and doesn’t let go, the brand’s innovative in-house Caliber 9R65 Spring Drive enables the Grand Seiko SBGA413 to not just match but even exceed the exacting timekeeping standards of its Swiss competitors.

Regarding the term “in-house”, let’s be clear: the 9R65 is not a lightly modified, off-the-shelf  ETA or Sellita movement like some Swiss brands use, but instead a groundbreaking, proprietary movement that combines both mechanical and electrical components to produce high-performance, quartz-like accuracy.

The Grand Seiko launched the Spring Drive in 1999, and since then the movement has gone through several iterations and improvements. The company officially calls the 9R65  version an “Automatic Spring Drive 3 Day” in reference to its robust 72-hour power reserve. 

It has hackable seconds and complications, including a quick set date and a power reserve indicator. There are 30 jewels, and the seconds hand oscillates at 32,768 Hz, which results in a gliding, shudder-free movement that, according to the company, symbolizes “the beautiful, natural flow of time.” The 9R65’s quartz-like accuracy is rated at an eye-popping +/- 1 second per day or +/- 15 seconds per month.

This amazing precision is accomplished by using a mainspring to store potential energy, which is released to power the movement, so it has no battery. Instead, it is hand-windable with a rotor for automatic winding just like a traditional mechanical movement. However, there is no escapement to control the speed of the energy release. 

In its place, Grand Seiko employs a “Tri-Synchro Regulator”, which, as the name implies, uses 3 types of energy to regulate the various components and processes that produce synchronicity:

1. The potential energy release from the mainspring;
2. A high-performance integrated circuit (IC) quartz oscillator that produces an electronic signal from the motion of the mainspring; and,
3. The transfer and synching of the electronic signal with a “magnetic brake” to control the spin of the glide wheel at exactly 8 revolutions per second which produces the amazing quartz-like accuracy.

If, like me, you’re neither an electrical engineer nor a certified watchmaker, you might need some illustrations and animations to help you get the full picture. Here’s a good video that does just that.

The 9R65 is not just a powerful and precise engine but also a work of fine art unto itself, as displayed through the sapphire caseback. Together with the beautiful textured, colorful dial, the result is the museum painting equivalent of two exquisite pieces of art on both the front and back of the frame. 

It is composed of over 200 colorful components that are hand-assembled. Polished parts and high-end finishing touches, such as diamond cut stripes, enhance the visual effect of the complex, intricate movement.

If Grand Seiko would just alter the display caseback and go a little lighter on the aforementioned brand lion logo in order to provide a less obstructed view of this showcase gem of a movement as they have in other models, the end result would be essentially perfect.

Bracelets and Straps

A watch with a finely manufactured and finished dial, case, and movement begs for a quality bracelet or strap to pair with it and bind the object of joy and satisfaction to the owner’s wrist.

The Grand Seiko Shunbun comes with a matching titanium bracelet with solid end links and a staggered alignment 3-link design with mostly satin brush finishing except for the edges of the center links, which are Zaratsu polished. 

That combination matches the case’s alternating finishes, and the polished edges contrast nicely with the rest of the bracelet. The bracelet is secured with a Grand Seiko logo stamped, single fold clasp with a twin-button release to prevent accidental opening. Rather than screws, the watch has a pin and collar system for link removal and sizing.  

Being titanium, it is naturally very lightweight, and it looks and feels like it has been manufactured with the same care and exacting standards as the rest of the watch.

However, if there is a “weak link” (heh) in the SBGA413, it is nevertheless found in the bracelet, which has a few quirks that the potential buyer should know about on the front end. For instance, the clasp does not sit completely flush with the bracelet but extends out slightly, increasing the chances of accidental snagging. 

There is no fine adjustment, a feature usually found on watch bracelets at most price levels, but there are two half links on each side of the clasp to improve the chances of a good fit. The lug width is the odd 21mm, making it harder to pair with after-market straps than watches with 20 or 22mm lug widths. 

But, many companies are starting to offer more 21mm choices in popular material, style, and color options. Also, some have noted slightly loose tolerances between the end links and watch case, and in their opinion, a little too much gap and jiggle for a $6000 watch.

Still, we’re really using a fine-tooth comb and a microscope to find such minor flaws. The bottom line is that the bracelet is of top-notch quality and pairs very well—if not perfectly—with the watch it holds.

On-Wrist Experience

My local Grand Seiko AD didn’t have a Shunbun in their showcase but did have another all-titanium Heritage Collection model with the same case style and a Spring Drive available to try on. If you’re accustomed to the heft of stainless steel and haven’t tried on a titanium watch before,  “heads up” because it can be a little trippy. 

My first impression was: Whoa, that thing is so light it practically flies out of my hand! But don’t mistake “lightweight” for “cheaply made” because Grand Seiko is a top-level luxury watch brand.

Beyond the comfortable featherweight feel, the watch fit well inside the width of my 6.5-inch wrist, even with the solid end links and 21mm lug width that slightly increase its presence. The short lug-to-lug distance of 46.5mm allows an acceptable fit on wrists of 6 inches or even slightly smaller, and the no-bezel design allows the watch to stand out on larger wrists in the 7.5-inch range. 

The slim Spring Drive and case design allow for a slender 12.8 mm thickness, so there is no problem fitting this watch under a cuff—although you’ll probably be constantly sliding it down to bare wrist in order to show it off to others, not to mention stare at it yourself.

Price & Availability

The Grand Seiko SBGA413 retails for $6,600. Per Watchcharts.com, the average preowned price as of this writing is $4,654, with an approximate range of $4,275-$5,000. The Shunbun is readily available at many Grand Seiko Authorized Dealers, including Exquisite Timepieces.

Conclusion

As I mentioned in the beginning, during the course of researching and writing this review, Grand Seiko became a “time tutor” who taught me seasonal change is more like a full chorus than a quartet. 

The luxury brand’s SBGA413 Shunbun is an ornate, highly accurate, and versatile watch suitable for many occasions. But it’s more than that: it’s a beautiful piece of “wrist art” with nuances you can savor and philosophical lessons about the “nature of time” you can learn and then live out.

To riff on a tagline for another highly accurate watch from a different era:  “It’s not a timepiece. It’s a contemplation piece.”