Seiko's take on the dive watch combines equal measures of fidelity to the class standards and unorthodox additions distinctive of the Grand Seiko tradition. With a 200-meter rated depth, titanium construction, and Seiko's signature Spring Drive movement technology, the Grand Seiko Spring Drive Diver 200M offers an impressive alternative to the Swiss dive segment stalwarts.
Seiko launched the titanium SBGA031 and its stainless steel SBGA029 counterpart at Baselworld 2012. The titanium utility watch attacked the saturated dive watch market with a compelling tandem of unique technology and unarguable utility. Seiko equips the Spring Drive Diver with an impressive array of useful functions that render it equally compelling to SCUBA divers and desk divers alike.
The bracelet and clasp are nothing if not over-engineered. A deployant clasp matches the standards for this class of watch, but it exceeds them in surprising fashion by matching a twin-trigger clasp release with a robust clamshell lock for absolute security and freedom from accidental opening. Once open, a second trigger releases the incremental dive extension: well over 20mm of extra length deploys for easy fitment over a dive suit or - more likely - a thick winter coat.
The entire bracelet is hand-finished in a combination of satin and polished titanium; this Grand Seiko features the same techniques on its substantial 44.2mm case. The watch wears well on a smaller wrist (i.e. 14-16cm circumference) thanks to the lightweight titanium construction, but the imposing 53mm span between bracelet solid end links ensures that it appears well matched on very large forearms as well.
Seiko employs a hard-anodized bezel on the premise that unlike ceramic, the anodized surface cannot fracture and separate from the watch while in use. A sapphire crystal with an inner anti-reflection coating straddles a matte-black lacquered dial base. Seiko uses applied polished indices with its proprietary Lumi Brite luminescent paint. Titanium hour and minute hands sport handsome satin finish and faceting. Gilt-style Seiko and Grand Seiko dial signatures provide welcome chromatic contrast and an upscale appearance.
Nevertheless, the face of this Grand Seiko Spring Drive Diver is not without its charming quirks. Seiko's selection of broad arrow and cathedral styles for the minute and hour hands, respectively, is an off-beat decision that instantly breaks with Swiss conventions. Moreover, the off-center power reserve scale at seven o'clock is a rare but welcome companion on a diver. While ISO 6426 (established 1996) defines a dive watch as one with a "constant operation" - generally seconds - indicator, knowing that a watch is close to stopping can be just as useful as knowing whether it is stopped; such information could have a bearing on safety if noted immediately before a dive.
Seiko graces the SBGA031 with Spring Drive, a flagship technology shared with Seiko Credor models priced in the hundreds of thousands of dollars. As featured in the Spring Drive Diver, the namesake technology is embodied within the automatic caliber 9R65. Far from a machine-made quartz, this is a hybrid system built and adjusted by a watchmaker; its 276 parts and 30 jewels contain an immense amount of traditional mechanical watchmaking.
The competitive advantage of Spring Drive derives from Seiko's conversion of spring energy into induced electrical current. The current activates a quartz oscillator, and back-EMF phenomena accelerate or slow a uni-directional regulator wheel that meters the spring energy to the watch's going train. Spring Drive's visual signature long has been the smooth circuit of its seconds hand which moves without detents or steps. And with a rated precision of +/- 15 seconds per month, the system easily upstages traditional chronometers.
It's difficult to envision a single target clientele for this Grand Seiko. While recreational divers are a natural match, the watch defies dive class norms with distinctive character, immense technology, and an unusual brand name that remains rare in Western markets. One fact is beyond dispute; divers, engineers, watch nerds, and horological Otaku will find plenty to love.