Throughout the 1960s and ’70s, Grand Seiko dedicated itself to crafting automatic and manually wound ten-beat timepieces, aiming for enhanced rate stability and precision. Now, after over 50 years, Grand Seiko unveils a new hand-wound high-beat movement, Calibre 9SA4. This marks the third addition to the latest generation of the mechanical Calibre 9S platform, which debuted in 2020 with the automatic Calibre 9SA5 and was followed by last year’s introduction of the Tentagraph Calibre 9SC5 chronograph.

Similar to Calibre 9SA5, the new 9SA4 operates at a frequency of ten beats per second and boasts an 80-hour power reserve when fully wound, courtesy of its highly efficient Dual Impulse Escapement and twin barrels. Both movements feature the Grand Seiko Free-sprung Balance and a hairspring with overcoil, ensuring stability, resistance to external influences, and superior performance synonymous with Grand Seiko’s high-beat movements. Calibre 9SA4, like other Grand Seiko mechanical movements, undergoes rigorous testing in six positions at three temperatures over a 17-day period to meet the brand’s exacting standards.

While sharing many traits with the 9SA5, the redesigned Calibre 9SA4 sees nearly 40 percent of its base movement reconstructed, with meticulous attention given to enhancing the tactile, auditory, and visual aspects of the winding experience. Notably, the movement’s click (a crucial component preventing the mainspring from unwinding) has been refined to perfect its feel and sound. The crown halts when the movement reaches full power. The click is fashioned in the shape of a wagtail, a bird symbolic of Morioka, the city near the Grand Seiko Studio Shizukuishi where all Grand Seiko mechanical watches are meticulously made.

The redesigned movement allows for the distinctive bird-like pecking motion of the click to be visible through the sapphire crystal case back during winding, complemented by delicate finishing inspired by the Shizukuishi River, capturing the natural beauty of the studio’s surroundings. A power-reserve indicator is kept off the dial and moved to one of the movement bridges. Furthermore, improvements in the gear train layout and component redesign enhance winding efficiency, enabling Calibre 9SA4 to achieve an 80-hour power reserve with 15 percent fewer crown rotations compared to Calibre 9SA5. Thanks to this slimmer architecture, Grand Seiko’s newest mechanical timepieces, both inspired by birch trees, boast a diameter of 38.6mm and a thickness of just 9.95mm. Ensuring comfort and stability, the watch’s center of gravity has been lowered, consistent with the renowned standards of Grand Seiko’s Evolution 9 creations.

The debut of Calibre 9SA4 will accompany a new dress watch design from the Evolution 9 Collection, continuing Grand Seiko’s iconic lineage tracing back to the legendary 44GS from 1967. This time, the Evolution 9 Style undergoes further refinement to embody the charm, elegance, grace, and subtlety expected of a hand-wound dress watch. The design has been carefully reassessed, with features such as the grooved indexes slimmed down and elongated, and the multifaceted lugs narrowed with reduced surface area to enhance the watch’s aesthetic appeal.

Crafted from Grand Seiko’s Brilliant Hard Titanium, the case  of SLGW003 exhibits a luminous quality surpassing traditional titanium, enhancing the Zaratsu-polished surfaces with a captivating radiance. This material not only ensures lightness but also provides highly resistance to corrosion and scratches, with a hardness double that of standard stainless steel. Additionally, the limited edition SLGW002 features a case and clasp crafted from 18k rose gold. This limited edition in precious metal shares the same dial color and pattern as its Brilliant Hard Titanium counterpart but is distinguished by gold hour markers.

Inspired by the slender white birch trees abundant in northern Japan and flourishing near the Grand Seiko Studio Shizukuishi, both watches capture the intricate texture of the birch tree’s bark in a completely new dial pattern.

Both timepieces will be available in August 2024, with the rose gold SLGW002 limited to just 80 pieces exclusively available at Grand Seiko Boutiques. The Brilliant Hard Titanium SLGW003 will join the mainstay Evolution 9 Collection and will be available at Grand Seiko Boutiques and select retail partners worldwide.