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You are here: Home / Movements / Seiko 9S64

Seiko 9S64

Last Update: February 1, 2020

Brand:Grand Seiko, Seiko, Shizukuishi Watch Studio
Family:
Seiko 9S6x Family
Height:
Jewels:24
Reserve:72 hours
Frequency:28,800 A/h
Winding:Hand winding
Diameter:
© 2013 Seiko  Complications:Hacking Seconds
Hands:Central Hour Hand, Central Minute Hand, Central Seconds Hand
Distinguishing Technical Characteristics
Hand-Winding
Clockwise Balance Cock
Screw Regulator
Balance
Balance at 1:30
Production: 2011 – Current
1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s 2000s 2010s 2020s

Cal. 9S64 is a hand-winding time-only movement from Grand Seiko. It is extremely unusual in the family, lacking a date and being hand-wound. When it was introduced in late 2011 it was the only hand-winding movement in the line until the derived Cal. 9S63 was introduced in 2019.

Cal. 9S64 is used in the Grand Seiko SBGW line of watches in the Elegance collection.

Most examples of Cal. 9S64 are accurate to -3/+5 seconds per day when static. The special model SBGW251 was tuned for -1/+5 seconds.

Seiko 9S6x Family Overview

9S is the family of high-end mechanical watch movements used in the Grand Seiko and Credor watch lines. The current “3 days” 9S6x family debuted in 2006 with Cal. 9S67, and has replaced the Seiko 9S5x series over the following decade. The movement boasts 72 hours of power reserve thanks to a stronger Spron 510 or 610 mainspring and escape wheel and pallet form finished with MEMS technology.

Seiko boasts that these movements can deliver -3/+5 seconds per day accuracy in controlled static tests. On the wrist, the company claims -1/+10 second accuracy per day, and Seiko adjusts them in 6 positions. Adjustment is performed using a screw with index moving a mobile regulator for the flat hairspring.

The 9S family movements are constructed by hand at Seiko’s Shizukuishi Watch Studio in Morioka, Iwate Prefecture, Japan.

All watches in the 9S6x series feature hand winding, hacking seconds, and operation at 28,800 A/h. Most feature automatic winding with a central rotor mounted on five ball bearings. These use a conventional reverser wheel rather than the Seiko Magic Lever system found on the previous Cal. 9S5x series.

Seiko 9S6x Family

ProductionModelsWindingJewelsDateNotes
Cal. 9S612015-presentSBGRAutomatic33No
Cal. 9S632019-presentSBGKManual33NoPower reserve at 3:00
Small seconds at 9:00
Cal. 9S642011-presentSBGWManual24No
Cal. 9S652010-presentSBGRAutomatic35Yes
Cal. 9S662010-presentSBGMAutomatic35YesCentral GMT hand
Cal. 9S672006-2010SBGLAutomatic41YesPower reserve at 3:00
Cal. 9S682017-presentSBGRAutomatic35YesLarger size

See Also: Seiko 9S6x Family

Images are taken from official publications and are used here for commentary and educational purposes. Copyright is held by the original owner as noted.

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