THE STORY OF THEGRAND SEIKO,FROM THE PAGESOF WATCHTIMEMAGAZINE

THE WORLD OF F INE WATCHES

SEIKOSEIKO

SPOTLIGHTwww.watchtime.com

EIKO’SGRAND PLANFor 50 years, to get a Grand Seiko, youhad to go to Japan. Not anymore.BY JOE THOMPSON

Assembling a Grand Seiko movement at Morioka SeikoInstruments

CLOSE-UPSeiko’s Grand Seiko

ast fall I made back-to-back reportingtrips, first to Japan, then to Switzerland.On the Swiss trip, in a meeting with aprominent CEO of a Swiss watch brand,the subject of Japanese watches cameup. Unprompted, he declared “Seikomakes the best mechanical watch in theworld. I hate to say it, but it’s true.” Hewas referring to the Grand Seiko, a lux-ury mechanical watch that Seiko hasproduced in Japan for 52 years for theJapanese market.

Two days later, in a conversationabout my travels with the technical di-rector of another Swiss watch firm, hesaid, unprompted, “I would love to havea Grand Seiko.”

Behind the scenes and off the record,such heresy is not unheard of in Switzer-land. In the Mecca of mechanical watch-making, one occasionally encountersopen admiration for a watch that is aparadox — an expensive, small-batch,chronometer-quality mechanical madeby the world’s most famous producer ofquartz watches.

In watch circles, Grand Seiko enjoyssomething akin to cult status. One rea-son is its exotic Japanese origins: GrandSeikos contain hand-made manufacturemovements with Seiko-made compo-nents, including hairsprings. Anotherreason is its rarity: Seiko barely makesenough Grand Seikos for Japan and acouple of other Asian markets. Butmostly its cult status stems from its per-

formance: Grand Seiko’s claim to fameis that each one must pass a battery oftests more rigorous than Switzerland’sCOSC conducts for its officialchronometer designation. Seiko calls thetests, which it performs itself, the GrandSeiko Inspection Standard. Seiko doesn’tovertly claim that Grand Seikos are bet-ter than Swiss mechanicals, but it comesclose. “The very best of mechanicalwatchmaking” is how Seiko phrases it.It leaves it to others, such as watch col-lectors who buy Grand Seikos on visitsto Japan and sing their praises on vari-ous watch websites, to make the claimfor them.

Now foreigners no longer have totrek to the Orient to seek this object ofwatch-collector fascination. In a dra-matic break with a half-century of tradi-tion, Seiko announced in 2010 that itwould sell Grand Seikos on 20 globalmarkets. Four models are now availablein the United States, ranging in pricefrom $4,400 to $25,000. The latest ar-rivals are the 130th Anniversary Com-memorative Edition, which is a replicaof the original Grand Seiko watch of1960. (The anniversary reference is tothe founding of the Seiko firm by Kin-taro Hattori in Tokyo in 1881.) Thewatch features a new hand-wound me-chanical movement, Caliber 9S64, andcomes in three limited-edition versions:stainless steel (1,300 pieces at $6,500),18k yellow gold (130 pieces at $16,500)and platinum (130 pieces at $25,000).The other models are the Grand SeikoHi-Beat 36000 watch with a new auto-matic movement with a frequency of36,000 vph ($7,200); three Grand SeikoAutomatics ($4,400 and $5,100); and aGrand Seiko Automatic GMT ($5,500).

The decision to distribute GrandSeiko internationally is the latest step inSeiko’s effort over the last decade to ele-vate the brand’s image by showcasing itsability to make luxury watches in addi-tion to its standard quartz fare. In recentyears, Seiko has launched on global mar-kets Kinetic, Spring Drive and even afew mechanical watches priced above$1,000. The arrival of Grand Seiko me-chanicals is the piece de resistance inSeiko’s grand brand-elevation plan.

Yellow gold andplatinum GrandSeikos from the

130th AnniversaryCommemorativecollection and themovement thatpowers them, Caliber 9S64

SPECS

GRAND SEIKO 130TH ANNIVERSARY COMMEMORATIVE COLLECTION

Manufacturer: Morioka Seiko Instru-ments, 61-1, Itabashi, Shizukuishi-cho,Iwate-gun, Iwate, Japan

Reference number: SBGW033

Functions: Hours, minutes, seconds

Movement: Caliber 9S64, manual-wind-ing; diameter = 28.4 mm; height = 4.9mm; 24 jewels; 146 components;Spron610 balance spring; 28,800 vph; 72-hour power reserve; magnetic resistance= 10,000 A/m

Case: Stainless steel; diameter = 35.8 mm;high definition dual-curved sapphire crys-tal with nonreflective coating; 30-meterwater-resistance

Strap and clasp: Crocodile with stainlesssteel buckle

Rate: Mean daily rate between -3 to +5seconds per day under static conditions;between -1 to +10 seconds per day whenthe watch is worn

Variations: Limited edition of 130 piecesin 18k-yellow gold ($16,500); limited edi-tion of 130 pieces in platinum ($25,000)

Limited edition of 1,300 pieces

Price: $6,500

CLOSE-UPSeiko’s Grand Seiko

The original GrandSeiko watch from 1960

The first watch to carrythe Seiko brand, 1924

Seiko’s first wristwatch,the Laurel, from 1913

SEIKO HAS MADEMECHANICAL WRISTWATCHESSINCE 1913 –LONGER THANMOST SWISSWATCH COMPANIES.

The strategy has its critics, of course.“There is only one thing wrong withGrand Seiko,” the Swiss CEO who soadmires it said with a Cheshire-catsmile: “The name!” His point is that forall Grand Seiko’s technical merits, con-sumers outside of Seiko’s home marketwill be loath to spend $4,000-plus for asteel mechanical watch (let alone$16,000-plus for a gold one) bearing abrand name they have long associatedwith mass-produced quartz watches.

THAT SEIKO even makes mechanicalwatches, let alone chronometer-qualityones, will come as a surprise to manypeople, who only know it as the brandthat launched (in 1969) and led thequartz-watch revolution. But there is farmore to Seiko than just quartz. SeikoWatch Corp.’s proudest boast is that thegroup is the world’s only watch produc-er to master four timekeeping technolo-gies: quartz, Kinetic, Spring Drive andmechanical. (Two of those, Kinetic andSpring Drive, are exclusive to Seiko.) In

Seiko began making mechanicalwatches, pocketwatches then, in 1895. Ithas been making mechanical wristwatch-es longer than most Swiss watch compa-nies. Next year it will celebrate the 100thanniversary of the Laurel, the first wrist-watch made in Japan. (For reasons un-known today, Seiko’s custom from thebeginning was to give new products Eng-lish names. “Perhaps Kintaro was alreadythinking of future export possibilities,”writes Masaharu Nabata in The SeikoBook: The Real History of Seiko Watch-es.) Most Swiss watch companies did notbegin producing wristwatches until afterWorld War I. The Laurel, Nabata writes,most likely contained components madeentirely in-house. By 1913, Seikosha, asthe company was called, was making itsown balance springs and enamel dials.The first watch to carry the Seiko namewas a wristwatch with a small secondshand at 6 o’clock that debuted in 1924.In 1937, Seiko created a second factory,Daini Seikosha (literally “SecondSeikosha”) exclusively for watch produc-tion.

World War II crippled Seiko’s watch-making development. Production shiftedto military products during the war; af-terward, the Japanese watch industryhad trouble rebounding. It wasn’t until1954 that Seiko achieved its pre-warproduction level of 100,000 watches permonth. In the mid-1950s, however,Seiko went on a crash program to raiseits mechanical watchmaking expertise toworld-class standards. It was that tech-nical push that led to the creation of theGrand Seiko series.

A turning point in Seiko’s mechanicalwatch history was the Seiko Marvel of1956, a 17-jewel manual-wind with an11.5-ligne movement that represented aquantum leap in accuracy for Japanesewatches. Seiko entered the watch in do-mestic watch competitions sponsored atthe time by the Ministry of InternationalTrade and Industry. The Marvel lived upto its name. It took the top five placesand seven of the top 10 in the 1957 com-petition. In 1958, it took nine of the top10 spots. The next year Seiko introducedthe Gyro Marvel, with an automaticmovement containing a major mechani-

cal innovation that is a Seiko exclusive,the Magic Lever. (It’s a device that in-creased the transfer of power to themainspring and delivered faster windingspeed. It did so by harnessing all the en-ergy created by the rotor as it revolves inboth directions. Seiko calls it “one of thekey breakthroughs in the modern histo-ry of mechanical watchmaking”; it isstill used in most Seiko automatics to-day.) In this period Seiko producedwatches like the Cronos and Crown thatare prized by Seiko collectors today.

fact, Seiko has a long history as a me-chanical watch producer. Today the gi-ant Seiko Group is a totally vertically in-tegrated mechanical watch manufac-ture. It produces mechanical watchesacross the price spectrum, from inex-pensive, mass-produced, automaticwatches called Seiko 5 at the bottom ofthe price pyramid to Grand Seikos at thetop. It makes all the components andmovements in-house. Americans are notfamiliar with the mechanical side ofSeiko because, until recently, none weresold here.

The Grand Seiko Automatic

GMT ($5,500)

The Grand Seiko Automatic ($4,400)

CLOSE-UPSeiko’s Grand Seiko

Flush with the success of these prod-ucts, Seiko felt ready to take on theworld champions in mechanical watch-making, the Swiss. Seiko assembled ateam of its top watchmakers on a projectto create what they called “an idealwatch.” The goal was to produce themost accurate, durable, legible and easi-est-to-wear watch in the world. This wasGrand Seiko. Writes Nabata, “All thetechnicians involved with the develop-ment of Grand Seiko knew that theirgoal was to exceed Swiss chronometerstandards. The company set out to makeGrand Seiko watches to a standard high-er than any timepieces ever made beforein Japan; Swiss chronometer standardswere the key to this ambition.”

Grand Seiko debuted in Tokyo onDec. 18, 1960. The original watch had amanual-wind movement, Caliber 3180,with a frequency of 18,000 vph. Itsstyling was sleek and simple and it car-ried the designation “chronometer” onthe dial. The emphasis was clearly on themovement. Despite a gold-filled case,the watch sold for 25,000 yen, equiva-lent at the time to two months’ salary ofa college-educated professional. Seikoput the watches through a testing regi-men more rigorous than that of Switzer-land’s COSC. Today, Grand Seikos are

SEIKO HAS JOINEDZENITH IN THE PRESTIGIOUS 36,000-VPHCALIBER CLUB.

Seiko’s automatic Caliber9S85 (below, left), with a frequency of 36,000 vph,powers the Grand SeikoHi-Beat 36000.

SPECS

GRAND SEIKO HI-BEAT 36000

Manufacturer: Morioka Seiko Instru-ments, 61-1, Itabashi, Shizukuishi-cho,Iwate-gun, Iwate, Japan

Reference number: SBGH 001

Functions: Hours, minutes, seconds, date

Movement: Caliber 9S85, automatic; di-ameter = 28.4 mm; height = 6.0 mm; 37jewels; 221 components; Spron530 bal-ance spring; 36,000 vph; magnetic resist-ance = 4,800 A/m; 55-hour power reserve

Case: Stainless steel; high-definition dualcurved sapphire crystal with nonreflec-tive coating; screw-down crown; exhibi-tion back; 100-meter water-resistance

Bracelet and clasp: Stainless steel, three-fold clasp with push-button release

Rate: Mean daily rate between -3 to +5seconds per day under static conditions;between -1 to +10 seconds per day whenthe watch is worn

Dimensions: Diameter = 40.0 mm; height= 13.0 mm; weight = 151 grams

Price: $7,200

CLOSE-UPSeiko’s Grand Seiko

Seiko makes its own hairsprings using an in-housealloy called Spron.

Grand Seiko watches and movementsare assembled by hand in Seiko’sShizuku-ishi Watch Studio.

Making wristwatches at Daini Seikosha in Tokyo in the late 1930s

tested in more positions, at more tem-peratures, for more days. (See “StandardProcedures: Seiko versus COSC” side-bar.) After a couple of years, Seiko re-moved the “chronometer” designationfrom the dial since the watches weretested at a standard greater than the in-ternational standard.

Seiko produced the first generationof Grand Seikos from 1960 to 1975.Seiko itself caused Grand Seiko’s demise:the company’s pioneering advances inquartz watch technology killed demandfor mechanical watches. It stopped mak-ing Grand Seikos in 1975. By the early1980s it halted virtually all mechanicalwatch production.

Miraculously, a decade later, Seikomechanicals came back, when the trustytick-tock found new life as a luxuryitem. In 1991, Seiko resumed full-scalemechanical-watch production. In 1998,Seiko launched a second generation ofmechanical Grand Seiko watches with anew mechanical caliber, the 9S5 series ofautomatic and hand-wound calibers, re-served exclusively for Grand Seikos.(Seiko had relaunched the Grand Seikoseries in 1988, but with quartz move-

SEIKO IS A COMPLETELY VERTICALLY INTEGRATED MECHANICALMANUFACTURE, MAKING ITS OWNCOMPONENTS FROM HAIRSPRINGSTO CASES AND BRACELETS.

CLOSE-UPSeiko’s Grand Seiko

“WE ARE TRYINGNOW TO INTEGRATE OUR COLLECTIONS TO PRESENT ONE NEW SEIKO TO THE WORLD.”

The man backing Seiko’s push to show-case its luxury mechanical watches onworld markets is Shinji Hattori, chair-man of Seiko Holdings Corp. and CEO ofSeiko Watch Corp. Recently WatchTimeeditor-in-chief Joe Thompson met inTokyo with Hattori, great-grandson ofSeiko founder Kintaro Hattori, to dis-cuss mechanical watchmaking. The fol-lowing is an excerpt from the interview.

WT: Why has Seiko decided to make apush into the luxury mechanical watchsector in recent years? SH: The main reason is globalization andthe maturing of the image of Seiko. Foryears there were, effectively, two Seikos.One was in Japan, where we have hadGrand Seiko for more than 50 years, aswell as the Credor brand. But there was adifferent Seiko in the rest of the world,where we have been the leader in mid-range quartz watches. In today’s global-ized world, many people from outsideJapan see and like our higher priced,high-grade Japanese models, and so weare trying now to integrate our collec-tions to present one new Seiko to theworld.

WT: What are the benefits of thisstrategic decision for Seiko? And whatare the risks? SH: There are risks, of course. We cannotexpect consumers in the U.S.A. to immedi-ately accept Seiko at prices 10 timeshigher than the current prices, but, overtime, we will get there. And the benefitsare huge. We will be able to raise the aver-age price of what we sell as the propor-tion of higher-priced merchandise increas-es, and we will achieve synergies in ourproduction by rationalizing the two collec-tions into one.

WT: From a product developmentstandpoint, does Seiko intend to pro-duce a full range of mechanical watchproducts, including high complica-tions? Or does Seiko plan to specializein a certain segment of the mechanicalmarket?SH: For Seiko, the accuracy is very im-portant. The word seiko in Japanesemeans “precision.” Our strength is inthis area of uncomplicated, high func-tionality, as you know from Grand Seiko.So, yes, we will produce a very smallnumber of complications under the Cre-

Shinji Hattori: No More Two Seikos

dor brand as you have seen in recentyears. [Editor’s note: the reference is tothe Credor Spring Drive Sonnerie andMinute Repeater watches.] But the coreof our offer in mechanical watches willbe high-quality watches that deliver in-dustry-leading accuracy over time andwhich are reliable, durable and simple.

WT: Are there particular Seiko mechan-ical watch projects that you are pleasedabout? SH: There are many! The recent Credorpieces made by the Micro Artist Studioare very special and have had a major im-pact on the luxury market. But perhapsmost of all, I am proud of the GrandSeiko Hi-Beat watch we launched in2010. I believe that the hi-beat mechani-cal caliber is the highest form of thewatchmaker’s art, as it requires excel-lence in every aspect: engineering preci-sion, materials and innovation. I believeour hi-beat caliber to be one of the verybest mechanical calibers in the world.

WT: Seiko has a tradition of innovationin quartz watch technology. Will thesame go for mechanical watchmaking?

SEIKO WATCH CORP. CEO SHINJI HATTORI

ments. To this day, the Grand Seiko linein Japan includes quartz and SpringDrive models.) In 2006, Seiko upped theante with a new caliber, the 9S6 series,with a 72-hour power reserve.

TO FIND OUT what makes the GrandSeiko so grand, you travel north out ofTokyo 340 miles to the mountainousIwate prefecture on Japan’s northeastcoast. In the center of the prefecture isthe city of Morioka, with majestic viewsof nearby Mount Iwate. The city ofShizuku-ishi, just outside Morioka, isthe home of Morioka Seiko InstrumentsInc. MSI is a powerhouse in Seiko In-struments Inc., one of the two giantwatch-producing companies in the SeikoGroup. (The other is Seiko Epson.) Thefactory, with 550 employees and 30,000square meters of floor space, churns out10 million watches a month. These arethe quartz pieces that made Seiko worldfamous.

Within MSI, however, there is anoth-er world. It’s called the Shizuku-ishiWatch Studio. Here a staff of 60 highlyskilled watchmakers and techniciansmake watches the old-fashioned way.The Watch Studio is a full-fledged man-ufacture, the only one in Japan. Here,says an MSI executive, “we develop, wedesign, we manufacture and we assem-ble luxury mechanical watches.”

At spotless workbenches in a large,spotless room, 19 watchmakers manu-facture mechanical watches, one by one,by hand.

Attached to each watchmaker’s spa-cious desk (the word “workbench”doesn’t do it justice) is a plaque with thewatchmaker’s name in Japanese andEnglish. Each desk is customized for thewatchmaker. The lacquered wood desksand cabinets in the studio are IwayadoTansu, traditional craft furniture that isa specialty of the Iwate region.

The watchmakers make and finish thecomponents, they assemble the move-ment, and they adjust and regulate it. Us-ing customized tweezers, they adjust thecurves of hairsprings, made of an exclu-sive, Seiko-developed alloy called Spron,which are only 0.03 mm thick. Thentechnicians test the movement. A lot. The

SH: We are constantly innovating in me-chanical watchmaking. You can find manyexamples in our current mechanicalwatches. We have created new Spron al-loys for our springs. We have made signifi-cant improvements to the precision of ourcomponents with MEMS technology. Lastyear we introduced new calibers in GrandSeiko (9S64) and in Seiko (8R39). Our inno-vations are, however, not just innovationsfor their own sake. All contribute to betterprecision over time and that will always beour focus.

WT: Do you see any difference in ap-proach to mechanical watchmaking be-tween Japanese and Swiss producers?SH: There are more similarities than differ-ences because I think that our friends inSwitzerland and Seiko share a common de-termination to develop and expand themarket for high-grade watches. Perhapsone small difference is that Seiko designs,produces and assembles its high-end me-chanical models in house. We have alwaysdone so and we always will. And another isperhaps that we are always ready to lookfor radical solutions. For example, let’s lookat Spring Drive. When we sought to dra-matically increase the precision over timeof the mechanical watch, we looked notonly at refinements of existing technolo-gies. We looked at completely new ideasand Spring Drive is the result. It is a me-chanical watch with a totally new kind ofregulator and it delivers a level of accuracythat other mechanical watches can neverachieve.

WT: What are Seiko's top markets for luxury mechanical watches today?SH: For historical reasons, Japan is ofcourse the biggest market. After Japan,the other Asian markets are very good forGrand Seiko and our other high-end me-chanical lines. Many people in these mar-kets have been aware of Seiko’s excellencein prestige watches for many years andthat is why the take-up of Grand Seiko hasbeen so strong in markets like Hong Kong,Singapore, Taiwan and, in the near future,China and India. In Europe and the U.S.A.,it’s a longer road that we must travel, butwe have already about 60 retail partnersfor Grand Seiko outside of Japan and weare very pleased with our progress.

first round is for 300 hours, after whichthe watchmakers fine-tune the movementagain. At that point it is ready for its 400-hour Grand Seiko inspection. Move-ments that pass are then assembled byhand into a case that has been hand-pol-ished. Each steel, gold, or platinum case ispolished using a special technique calledZaratsu, or blade polishing, which cre-ates a flat, smooth, mirror finish. Thecomplete watch then gets a final inspec-tion. In total, every Grand Seiko watchspends more than 1,000 hours being test-ed and inspected. Each watch comes witha rating certificate certifying that it haspassed the Grand Seiko Inspection Stan-dard.

The Shizuku-ishi workshop pro-duces more than 20 different mechanicalwatch calibers in two families, Caliber68 and Caliber 9S. Caliber 68 is a seriesof movements used in thin mechanicaldress watches that Seiko sells in Japanunder the Credor label. Caliber 68 is anultra-thin, hand-wound movement just1.98 mm thick. The Caliber 9S series,which Seiko calls “the flagship ofSeiko,” is used exclusively in GrandSeiko watches. With all the handiworkinvolved in the calibers of both families,the manufacture’s annual output issmall. How small is a Seiko secret;Japanese sources put the number ofGrand Seikos produced per year in thethousands rather than tens of thousands.

Seiko created the Caliber 9S seriesfor the revival of the mechanical Grand

THE GRAND SEIKOTEST IS TOUGHERTHAN THE COSCTEST FOR SWISSCHRONOMETERS.

Seiko collection in 1998. The first move-ment, 9S55, was Seiko’s state-of-the-artmechanical movement, an automaticwith 50-hour power reserve. But to liveup to the Grand Seiko ideal, Seiko feltthe watch should run for an entire week-end without winding down. Theyachieved that in 2006 with a new caliber(the 9S6 series) that runs for 72 hours ona full charge. “The long power reserve of72 hours relieved a major concern,” saysone Morioka Seiko executive. “There is

no need to reset the hands on Mondaymorning, because the watch will contin-ue operating through the weekend.”Seiko says the improved power reserve isthe result of two major advances in com-ponent manufacturing at MSI over thepast few years. One is the introductionof Micro Electro Mechanical System(MEMS) engineering in parts produc-tion. MEMS is a technology developedfor the integrated circuit industry that isnow being applied to watchmaking. The

A Seiko watchmakerworking on the ultra-thin Caliber 68 used in Credor watches for the domestic market

A masterwatchma -ker at hisdesk in theShizuku-ishi WatchStudio atMorioka

The Morioka Seiko Instruments factory in Iwate Prefecture in

northern Japan

CLOSE-UPSeiko’s Grand Seiko

other involves improvements in Seikobalance springs and mainsprings madewith Spron, the highly elastic in-housealloy that Seiko Instruments developedfor mainsprings. MSI says Spron, whichis a registered trademark of SII, deliversmore torque and resistance to shock.

Calibers in the 9S6 series use alonger, wider, and thinner mainspringmade of Spron510, an improvementover the Spron200 mainspring in the9S5 series. Balance springs are made of

CLOSE-UPSeiko’s Grand Seiko

Spron610, with greater shock-resistanceand anti-magnetism (10,000 A/m).

The caliber also has a new MEMS-made escape wheel and pallet. Comparedto traditional machined parts, MEMStechnology produces components thatare lighter, more precisely cut and moredurable, with smoother surfaces. The re-sult, Seiko says, is greater accuracy.

Seiko uses the same technology in theGrand Seiko Hi-Beat 36000 watch in-troduced last year. Seiko is one of justtwo watch firms (the other is Zenith) tomanufacture a 10-beat caliber. High-fre-quency watches have better accuracy be-cause they deliver 50 percent moretorque than a standard eight-beat move-ment. The downside of 10 beats is a lowpower reserve and low durability.Seiko’s Caliber 9S85, however, managesa power reserve of 55 hours. Like othermembers of the 9S family, it has aMEMS-manufactured escape wheel andpallet and Spron610 balance spring. Themainspring is made of a new material,Spron530, which SII developed with theMetal Material Laboratory of TohokuUniversity in Sendai, Japan.

How does Seiko’s Grand Seiko InspectionStandard differ from the COSC tests re-quired for a Swiss mechanicalchronometer? In three ways, Seiko says.“The Grand Seiko standard involvesmore tests in more positions and atmore temperatures than today’schronometer standard,” Seiko says in astatement.

Here are the differences:1. Seiko tests its Grand Seiko movementsin six positions versus five for COSC.Both Seiko and COSC check the accuracy,or rate, of the movement in various posi-tions simulating the various angles awatch is in when on the wrist. Seiko,however, adds one additional position:the position of the watch when it is notbeing worn and placed vertically on aflat surface, crown right, with 12 o’clockat the top.

2. Seiko tests Grand Seiko movementswith two temperature variations versusCOSC’s one. Changes in temperature canaffect the performance of a watch. COSC

checks the thermal variation of dailyrate between 8 and 38 degrees Celsiusand requires that the rate variation notexceed +/- 0.6 seconds per day. LikeCOSC, Seiko checks thermal variation be-tween 8 and 38 degrees Celsius. ButSeiko conducts a second test for varia-tions between 23 and 38 degrees Cel-sius. The extra temperature rating iscloser to body temperature. Seiko has aslightly tougher standard than COSC, +/-0.5 seconds per day.

3. Seiko tests Grand Seiko movementsfor 17 days versus COSC’s 15. The two ex-tra days are for the test of the movementin the sixth position.

The Grand Seiko standard has beenrevised several times over the years. Thecurrent standard was set in 1998, whenSeiko revived the mechanical GrandSeiko collection with the Caliber 9S fam-ily of movements.

The following table outlines the dif-ferences between the COSC and GrandSeiko standards.

Standard Procedures: Seiko vs. COSC

TESTING PROGRAM/CRITERIA COSC CHRONOMETER GRAND SEIKO

Secs/day Secs/day

Mean daily rate -4 - +6 -3 - +5

Mean rate variation 2.0 1.8

Maximum rate variation 5 4

Maximum difference in rate between vertical and horizontal positions -6 - +8 -6 - +5

Greatest rate difference 10 8

Rate variation per 1°Cbetween 8° and 38°C -0.6 - +0.6 -0.5 - +0.5

Rate variation per 1°C between 23°and 38°C (not applicable) -0.5 - +0.5

Rate resumption -5 - +5 -5 - +5

Number of positions 5 6

Time period 15 days 17 days

Source: Seiko Watch Corp.

A Grand Seiko Hi-Beat watch with the Grand Seiko certificate