Let us begin with the meeting.
History of the model
- The 4420-9000 caliber is replaced by its more modern descendent, the 9S64,
- Mainly because of the caliber difference, the 1967 model thickness being 10mm and SBGW047 is 11.5mm,
- The 1967 model being acrylic glass and SBGW047 sapphire crystal,
- The Grand Seiko emblem on the case back was gold filled in the 1967 model and is stainless steel embossed in the SBGW47 model,
- The case is also proposed in pink, yellow and white gold versions while the original model was produced only in stainless steel.
Finally, Seiko proposes 4 limited editions:
- SBGW047 stainless steel case, limited edition of 700pcs worldwide (reviewed here),
- SBGW046 18K pink gold case, limited edition of 70pcs worldwide,
- SBGW044 18K yellow gold case, limited edition of 70pcs worldwide,
- SBGW043 18K white gold case, limited edition of 70pcs worldwide.
The case: “The Grammar of the Design”
- « Water proof » is replaced by « water resistant »
- The « stainless steel » indication is still present.
- The letter « A » as well as the encircled « A4 », that are found on the current model, are internal classifications to Seiko.
- The movement number (9S64-00G0 here) is necessarily different from the original model but still present,
- A specification of the magnetic resistance up to 4 800 A/m, not indicated of the 1967 model. This is in agreement with the ISO764:2002 standards.
- Finally, the reference number of the watch replaces the serial number of the original model.
The crown fits into a very light cutout and is integrated perfectly into the case.
The dial: sobriety and readability
The typography Grand Seiko and Diashock is printed as “Japan 9S64 00E0 R 3″ at 6 o’clock.
Hands and markers: light effects
The central second hand, of a much darker color, appears of a tungsten grey. It is blue on the white gold SBGW043 model, so as to differentiate the metal according to the references.
The caliber: a movement dedicated to Grand Seiko
- 24 jewels,
- frequency of 28,800 vph (4 Hz),
- diameter of 28.4 mm and width of 4.9 mm,
- power reserve of 72h thanks to a longer and thinner mainspring in « SPRON510 » alloy patented by Seiko. This is today, one of the longest power reserves on the market for a single-barrel movement.
- balance spring made in in « SPRON 610 » alloy, giving the timepiece improved shock resistance and anti-magnetism properties,
- pallet lever and escape wheel are created using Seiko’s MEMS technology (Micro Electro Mechanical System),
- accuracy from +5 ~ -3 seconds/ day,
- Diashok technology.
Band and buckle
Paris, France, 12-14-2014.
Diashock (non Seiko documentation)
COSC Vs. Grand Seiko chronometer standards
Studio Shizuku-ishi Watch
Grand Seiko Collection
Seiko Center Paris