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A Look Inside Grand Seiko’s 9F Quartz Movement

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Quartz watches tend to get a bad rep with watch lovers, but not all quartz watches are the same. Enter Grand Seiko. The high-end Japanese marque is known for their classic mechanical and Spring Drive calibers, but they also makes some of the most impressive quartz watches currently on the market. In fact, it’s not an understatement to say that Grand Seiko’s 9F quartz calibers, and the watches they live inside, are entirely different beasts altogether. These movements are built and finished to an exceptionally high standard, and they feature full-metal construction and utilize a catalog of in-house technologies to ensure long-term operation and highly-accurate timekeeping.  

Grand Seiko’s excellent 9F62A caliber.

The idea here, and this is something I heard directly from Grand Seiko’s engineers when I toured the company’s facilities last year, is that these movements are engineered much in the same way Grand Seiko’s mechanical movements are. To that point, they’re designed to be serviced should something go wrong mechanically, and they’re not meant to be discarded and replaced like many cheaper, mass-produced quartz movements are.

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But before we get to what makes these movements so good, let us first get some of the fundamentals out of the way: how does a quartz watch work?

All quartz movements make use of a quartz crystal, hence the name. Quartz crystals are piezoelectric, which simply means that if you apply mechanical stress to a piece of quartz it will accumulate an electrical charge. Conversely, if you apply electricity to a piece of quartz cut into the right shape — like a tuning fork — that piece of quartz will vibrate at a steady frequency. To be specific, the relevant frequency is 32,768 oscillations-per-second. Quartz watches make use of a small battery cell as their source of electricity.

The integrated circuit and quartz oscillator found inside the 9F movement (penny shown for scale).

But the crystal is just half of the equation — there’s also an electronic component to quartz watches. What makes the vibration of quartz especially interesting is that if you divide by half the aforementioned frequency of 32,768 oscillations-per-second 15 times, you arrive at the number one, or one second. This is the function of the integrated circuit in a quartz watch; it performs this calculation to reach that one. This information is then fed to a small step motor, which drives the hands on the dial-side of the watch.

These movements are engineered much in the same way Grand Seiko’s mechanical movements are. To that point, they’re designed to be serviced should something go wrong mechanically, and they’re not meant to be discarded and replaced like many cheaper, mass-produced quartz movements are.

Now that we have an understanding of the basics, let us explore what makes Grand Seiko’s 9F movements so distinct.

We’ll  start with the quartz crystal itself. Grand Seiko grows and ages their own quartz crystals for a period of three months, and they select only the highest quality and most stable crystals for use in their 9F calibers.

A Seiko-grown quartz crystal in varying states of finish.

Of course, quartz, like most things, is not without its shortcomings. Quartz is sensitive to temperature, and that sensitivity can in turn impact timekeeping. The engineers at Grand Seiko consider this, so they test each individual crystal for its response to fluctuations in temperature, and then pair each crystal with an integrated circuit that has been specifically programmed to work with the properties of that crystal. To ensure that temperature is not affecting timekeeping, the movement samples the ambient temperature 540 times a day, and if any deviation from the oscillation frequency is found, then the difference is immediately adjusted. This gets you incredibly accurate and consistent timekeeping, with Grand Seiko rating their 9F calibers to an excellent + or – 10 seconds a year. As a simple point of comparison, your typical run-of-the-mill quartz movement is rated to about 15 seconds a month.

But the quartz crystal is just the tip of the iceberg. Performance, and how that performance is expressed visually through the dial-side of the watch, was also taken into consideration by Grand Seiko’s watchmakers and engineers.

Have you ever noticed how most quartz watches have a second hand that seems to quiver when it tick across the dial? That’s caused by a backlash, and not only is it visually unattractive, it also means that more often than not the second hand will miss its marker. Grand Seiko’s engineers wanted to ensure this didn’t happen with their 9F caliber, so they designed a special gear equipped with a hairspring to minimize the backlash. This gear applies the small force of the coiled hairspring back to the gear train, eliminating that quiver. The added benefit is that the second hand also lands precisely on the second marker each and every time.

Gear equipped with a hairspring.
It applies the small force of the coiled hairspring back to the gear train, eliminating that pesky quiver.

The movement has a shielded construction to prevent dust from entering the module during battery change, which means that short of that battery change, you can go a long time without having to pop open the case back.

Also worthy of note, Grand Seiko quartz watches use the same broad, heavy hands that you see across their mechanical range, which is a good thing because it’s hard to imagine a Grand Seiko watch without the brand’s iconic handsets. A normal quartz movement would lack the necessary torque needed to support the weight of such hands, but Grand Seiko found the solution in the form of a twin pulse control motor. Here, the second hand actually moves two times per second, rather than just once. It happens so quickly that you’d never see it with the naked eye, and the first time I saw it myself was in a slo-mo video. Here, take a look.

Slowed down, you can see how the second advances twice per second.

By doing this, Grand Seiko’s engineers create the necessary higher torque without exhausting significantly more energy. The result is a still reasonable battery life rated to around three years of operation.

The fine regulator.

We’re not yet done with the features. There’s an instantaneous date change, not unlike what you would get with a mechanical movement. These movements also feature full-metal construction with striping, jewels, and even a fine regulator. 9F calibers also have a shielded construction to prevent dust from entering the module during battery change, which means that short of that battery change, you can go a long time without having to pop open the case back. Just to put a fine point on what I wrote above, this is a movement designed to be fixed should something go wrong, so you can expect many years of hard-wearing service, much like you would with a traditional mechanical caliber.

On the 25th anniversary of the 9F range last year, Grand Seiko released a line of quartz watches featuring a GMT complication. This was something Grand Seiko’s team had always planned on doing, but it was technically impossible at the outset of the project. There were two big challenges. The first was the aforementioned instantaneous date — an important 9F feature that could not be sacrificed. And the second was creating a durable enough leaf spring called a jumper that could withstand frequent use. In 2018, the component production technology team of the Shinshu Watch Studio, the place where Spring Drive and 9F calibers are made, finally solved these two technical issues, making the 9F GMT movement possible.

Grand Seiko Ref. SBGN005.

Since their introduction 26 years ago, Grand Seiko’s 9F calibers have shown what is truly possible with a quartz movement. From the build quality and aesthetics to the feature set and overall performance, these calibers should make even the most devoted mechanical die-hards take a second look. So the next time your mechanical-obsessed friend dismisses quartz movements as something lesser, you’ve got the horological knowledge to prove them wrong.

To read other installments in this series, click here. To explore Grand Seiko’s 9F Quartz range, visit Grand Seiko.

The movements and watches featured here are instructional samples. No Grand Seiko watches or movements were hurt in the making of this series.

Ilya is Worn & Wound's Managing Editor and Video Producer. He believes that when it comes to watches, quality, simplicity and functionality are king. This may very well explain his love for German and military-inspired watches. In addition to watches, Ilya brings an encyclopedic knowledge of leather, denim and all things related to menswear.
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