9F Quartz Caliber

"Taking quartz into a new realm."

Quartz caliber 9F is astonishingly accurate, with gain/loss measured in just seconds per year, but time-keeping accuracy is just one aspect of the many that place it among the finest quartz movements in the world.

The Twin Pulse Control Motor allows the use of the long and wide hands for which Grand Seiko is known, an achievement that before 9F was only possible with the high torque of a mechanical movement.

The Backlash Auto-Adjust Mechanism enables the second hand to advance precisely with no shuddering, by incorporating a hairspring device traditionally used usually only in mechanical movements.

The Instant Date Change Mechanism changes the date display in 1/2000th of a second.

The Super Sealed Cabin prevents dust entering the movement when the battery is changed and prolongs the life of the lubricating oils that ensure smooth operation of the gear train.

This is a timepiece of exceptional quality with features that were previously unimaginable in a quartz movement. Combining superior functionality and meticulous detail, Caliber 9F takes the quartz watch into a new realm.

About Quartz Watches

The technologies unique to the world’s best quartz caliber

To create a quartz movement worthy of the Grand Seiko name, numerous new mechanisms were invented for Caliber 9F.

Twin Pulse Control Motor

The first challenge that the Grand Seiko engineers faced was the issue of the hands. It was essential that Grand Seiko had the same bold, impressive and long hands that are part of the Grand Seiko signature. However, no existing quartz movement could generate enough torque to move such heavy hands, so the engineers developed the ingenious Twin Pulse Control Motor, capable of turning longer and heavier hands while preserving battery power.

In a normal quartz movement, the second hand moves in a single step from one second to the next. In Caliber 9F, the second hand instead makes two consecutive steps per second, triggered by two successive pulse signals. Undetectable by the naked eye, this additional step enables the use of heavier hour, minute and second hands while preserving a battery life of three years.

Backlash Auto-Adjust Mechanism

Watch hands are driven by a series of gears, and there is always a certain amount of play, or backlash, between the teeth that engage each wheel with the next. Although this backlash allows the gears to rotate smoothly, it also makes the second hand shudder slightly, an imperfection that the engineers saw as incompatible with the precision of the caliber and the high standards of Grand Seiko.

In Caliber 9F, a special hairspring-equipped gear applies tension to the gear train and so minimizes the backlash. Using a device first developed for mechanical watches, this unique Backlash Auto-Adjust Mechanism brings a new level of precision to the way that the second hand moves.

Instant Date Change Mechanism

In normal quartz movements, the date change generally takes place over a period of hours during the night and the correct date is not fully displayed during the transition period. While there are some mechanical movements with enough torque to deliver instant date changes, this had never been achieved with a quartz movement.

With Caliber 9F, Grand Seiko succeeded in meeting the challenge resisted by every other manufacture: to create an instantaneous date change in a quartz movement.

The solution was found by developing a ‘date jumper’. This is a special mechanism that generates power as the date indicator driving wheel rotates, accumulating tension that is released instantaneously to drive the calendar wheel forward in just 1/2000th of a second. Using this mechanism, the date changes in the blink of an eye, for the first time in a quartz movement.

Super Sealed Cabin

Seiko developed the Super Sealed Cabin to guarantee that the precision of Caliber 9F continues to be as high as possible, year after year. This structure prevents dust from entering delicate parts of the movement when the battery is changed and ensures that the lubricating oil reserve for the step motor pivot is sealed from the air, extending the life of the oil.

Independent Axis Structure

A watch’s second hand makes 1,440 full revolutions every day and the minute hand completes 24 revolutions. Precise time can only be correctly displayed if there is no interference between these rotating parts.

In Caliber 9F, spacers are incorporated into the axis of each hand, preventing them from brushing each other, eliminating twitching when the time is adjusted and facilitating the smooth and precise movement of the hands.

Technologies for superior accuracy

Each Caliber 9F movement earns the title of Grand Seiko only after passing a rigorous process of multiple tests and inspections.

The outstanding quartz crystal exclusive to 9F is produced in-house.

Three-month aging

The accuracy of a quartz watch depends on whether the quartz oscillator can maintain a precise rate of 32,768 oscillations per second. Despite the overall regularity of this oscillation, each quartz oscillator in fact has different performance characteristics, and some turn out to be unable to maintain stable oscillation during the course of long use and changes in the environment.

In recognition of this, Seiko has developed a special selection process for quartz oscillators, known as “aging”. Groups of 32 high-quality quartz oscillators made in-house are first “aged” for three months, during which they are subjected to certain voltages so that their characteristics stabilize. Only then are they tested and selected, and only quartz oscillators that meet strict standards are used in Caliber 9F.

Automatic temperature monitoring and correction—540 times per day

Quartz oscillators are susceptible to temperature changes. The rate of 32,768 oscillations per second fluctuates with changes in ambient temperature. If this rate changes by even a single vibration per second, accuracy can fall by as much as 16 minutes a year.

To solve this problem, Caliber 9F measures the temperature inside the watch 540 times a day, compensating for any deviation and preserving the high accuracy.

Regulation switch

Just like a mechanical movement, Caliber 9F has a regulation switch for micro adjustment of accuracy. If, after years of use, a drift in timekeeping should ever become apparent, it can be corrected with this feature. However, given the superb inherent accuracy of Caliber 9F, most owners will never need to know this adjustment function even exists.

How a quartz watch works

A quartz watch uses a battery as its power source. The battery sends electricity to a quartz oscillator, which vibrates at precisely 32,768 times per second. An integrated circuit detects these vibrations and sends out an accurate time signal every second to the step motor. The step motor activates in accordance with this time signal, accurately rotating a series of gears and the watch hands.

The accurate, compact and light Grand Seiko Quartz Caliber 9F delivers an outstandingly high accuracy of +/- 10 seconds per year.