Hi-Beat 80 Hours Genbi Valley

Channeling the cool waters of Japan’s Genbi Valley

Japan’s lush Genbi Valley has been designated as a Place of Scenic Beauty and Natural Monument. This scenic gorge can be found mid-stream on the Iwai River in Iwate Prefecture, where expert craftspeople create Grand Seiko’s mechanical watches. This special place in Japan serves as the inspiration for this new Grand Seiko Evolution 9 Hi-Beat 'Genbi Valley' reference. 

The Genbi Valley’s flowing water in early summer is expressed through a unique pressed-pattern dial in light blue. Inside is the mechanical high-beat Caliber 9SA5, a Grand Seiko-exclusive self-winding movement. Thanks to the Dual Impulse Escapement and twin barrels, this mechanical movement achieves a high frequency of 36,000 vibrations per hour while offering an impressive power reserve of approximately 80 hours when fully wound. The watch’s case and bracelet are created from Ever-Brilliant Steel, a stainless-steel alloy renowned for its exceptional corrosion resistance and bright hue.

Born in the pursuit of the ideal wristwatch, the Evolution 9 Style evinces a new design grammar that evolved from the Grand Seiko Style of 1967. Through the Evolution 9 Style, Grand Seiko forges a new path while honoring its origins.

The Iwai River, which flows from its source on the northern slope of Mt. Kurikoma, eroded massive stones to shape the terrain and create waterfalls and ravines. This resulted in the Genbi Valley’s natural beauty. Its impressive scenery is celebrated through a designation as a Place of Scenic Beauty for Japan. This beauty inspired the pressed pattern dial with light-blue color, whose expressions are ever-changing depending on the angle of the light.

Thanks to the highly efficient Dual Impulse Escapement and twin barrels, Caliber 9SA5 achieves approximately 80 hours of power reserve when fully wound, even with its high frequency of 36,000 vibrations per hour. The mechanical movement also allows the watches it powers to be lighter, through a unique horizontal ring construction.

Known as Ever-Brilliant Steel due to its brilliant white hue, this special alloy is more resistant to corrosion than the stainless steels used in even the most prestigious watches today. It has a PREN (Pitting Resistance Equivalent Number) value 1.7 times higher than the grade of steel used in most high-end timepieces. PREN is a widely accepted standard used to measure corrosion resistance.

The tapered bracelet features a three-step micro-adjustment clasp that operates without a tool, allowing a total of 6mm of fine adjustment in precise 2mm increments.