Description
About Grand Seiko SLGH017
Grand Seiko Evolution 9 Collection
The dial inspired by white birch forests at night
This Hi-Beat 36000 watch shares the same Evolution 9 design as the celebrated ‘White Birch’ SLGH005 but is presented with a black dial that captures the atmosphere of the white birch tree forests on the Hiraniwa Plateau at night. These forests cover some 400 hectares and are located near the studio in Shizukuishi where all Grand Seiko mechanical watches are crafted.
Its powerful hands and grooved, prominent markers ensure perfect legibility. Its Zaratsu polished, distortion-free mirror finish and delicate hairline finish alternate to give the case a quiet and harmonious glow. The case has wide lugs and a low centre of gravity that ensure that the watch sits easily and securely on the wrist.
This high-beat watch is powered by the revolutionary Calibre 9SA5, which offers a power reserve of 80 hours thanks to the high efficiency of Grand Seiko’s unique Dual Impulse Escapement and the high power generation of the twin barrels.
About 9S Mechanical
In 1968, Grand Seiko introduced Japan’s first automatic 10-beat watch (61GS) to the world.
In 2009, 10-beat Caliber 9S85 surpassed the original, with high precision parts created using sophisticated modern technology assembled with skills honed over the many decades of Grand Seiko’s watchmaking.
Innovations to the precision controlling mainspring, the hairspring, and the escapement mean that the 9S Mechanical is not simply a revival of the 10-beat movement of the past, but an entirely new incarnation of this high-precision movement.
Grand Seiko SLGH017 Main Concept :
9SA5 the latest and finest Hi-Beat 36000 caliber.
This high-beat watch is powered by the revolutionary Caliber 9SA5, which offers a power reserve of 80 hours thanks to its enhanced energy efficiency. First presented in 2020, Caliber 9SA5 incorporates three significant developments, the entirely new Dual Impulse Escapement, the Grand
Seiko free-sprung balance, and the horizontal gear train which, together, set a new standard in high-beat horology. While offering advanced functionality, the caliber is slimmer than ever, giving the watch a slender profile.
MOVEMENT
36,000 vph, 80 hours of power reserve and a slim profile.
The challenge for any watchmaker who creates a high beat movement is to strike the perfect balance between precision, power and size without compromising on any of these parameters. In developing the 9SA5 caliber, the Grand Seiko development team set out to deliver the same level of stable accuracy as that of their existing 36,000 vph movement but to deliver a longer power reserve and so makes the watch even more practical in everyday life.
They succeeded in characteristically uncompromising style.
Caliber 9SA5 has a precision rate of +5 to –3 seconds a day and a power reserve of 80 hours.
The three technical advances that make the difference
1. Dual Impulse Escapement
The escapement is entirely new and was developed in-house. It enables the escapement wheel to transmit power directly to the balance, leading to an efficiency increase. It is unique in that, in one direction, power is transmitted directly to the balance while in the other it is via the pallet fork, as in a traditional escapement. Both pallet fork and escapement wheel are made using MEMS technology.
2. Grand Seiko Free-sprung Balance
9SA5 uses a new and special free-sprung balance developed for this caliber. It retains its precision for longer and is more resistant to shock and friction. While the current Caliber 9S uses a flat hairspring, 9SA5 uses an overcoil, whose curve shape was decided after more than 80,000 simulations with the result that its performance is optimized in every possible position. The uniqueness is that it can improve the isochronism. The secret lies in the precision manufacture of the components as well as the extraordinary adjustment skills of the watchmakers at the Grand Seiko Studio Shizukuishi.
3. Horizontal Gear Train
The new caliber is 15% slimmer than the current Grand Seiko high beat caliber, thanks to the innovative horizontal layout of the barrel and gear trains. In addition to these three new components, Caliber 9SA5 has other features that contribute to its extraordinary performance. Two barrels, arranged in sequence, enhance the power reserve, the date change is virtually instantaneous and the positioning of the winding stem close to the rotor allows the watch to sit closer to the wrist.
The movement is as beautifully finished as it is efficient. The bridge has a gently curving outline that is inspired by the shapes of Mt. Iwate and a bend in the Shizukuishi River that runs near the studio where the watch is made.
Grand Seiko SLGH017 Features :
- 47 jewels
- Date display
- Screw case back
- Screw-down crown
- See-through case back
- Stop second hand function
Grand Seiko SLGH017 History :
Prior to 1960, to challenge the status of Swiss watches and change the perception of Japanese watches, Daini Seikosha and Suwa began the discussion of a product line that can match the quality of Swiss watches under the suggestion of the parent company. At the time, Suwa Seikosha Co. was in charge of manufacturing men’s watches, so it was decided that Suwa would be producing the first Grand Seiko (GS).
The first Grand Seiko was released in 1960, it was based on Seiko’s previous high-end watch, CROWN. This Grand Seiko has a 25-jewel, manual-winding, 3180 caliber, and only 36,000 units were produced. This was also the first chronometer-grade watch manufactured in Japan, and it was based on Seiko’s own chronometer standard.
Design style
The design language of the Grand Seiko was set in 1967, with the creation of Grand Seiko 44GS. The 44GS set the ground for all future Grand Seiko with nine elements. These elements help improve the legibility of the watch under different situations, and create a sharp, crisp visual impression:
- Double width index at 12 o’clock
- Multi-faceted rectangular markers
- Highly polished bezel
- Highly polished planes and two-dimensional surface
- Half recessed crown
- Flat dial
- Multi-faceted hour and minute hands
- Curved side line
- Reverse slanted bezel wall and case side
- Dress style with simple but beautiful design
- Zaratsu polishing
source : wikipedia
