The caliber 9F62/82, a re-designed 9581A, has a Twin Pulse Control high-torque motor making each second move in two fluid pulses, thereby reducing energy consumption. A backlash auto-adjustment eliminates any error. If that is not enough, instantaneous date change happens in just 0.5 milliseconds. Furthermore, the movement module is air-tight, ensuring the stepper rotor and lubricants are protected from particles of dust. This last feature maintains optimal performance for an estimated period of 50 years before requiring a service.
One cannot ignore that the GS Quartz is the true GS, arguably more so than the modern mechanicals. In 1992, the last year of the 9587 production, the GS line was not only continued by the 9F movement but also extended by Grand Seiko reference SBGX, importantly, it is thinner, and uses more common parts, therefore the frame can be used for a number of other movements and watches. One might ask what is the difference between the 9F82 and the 9F62? Grand Seiko quartz movements are made in two different sized movement for different sized cases - how impressive is that..
The movement has a three-year power reserve via the battery and it is thermo compensated featuring a trimmer, so if you live in extreme environmental conditions or the quartz crystal is aging, the trimmer allows a watchmaker to adjust for the variation and that's a feature seen on precious few quartz movements - such as for example the Rolex Oyster quartz. This watch is much more accurate than the oyster quartz; the combination of the trimmer, the hand adjustment, the hand assembly and the thermal compensation means that this movement is accurate to plus or minus 10 seconds per year and you've got a quick set system for a date that is itself adjusted by a watchmaker who only performs adjustment on these 9F dates - it's a lever and cam system with a spring jumper which changes precisely right around midnight at the same time every night between 12:00 and 12:05 a.m. and it's usually at about 12:02 that it jumps and pops like a rifle bolt. This movement however is not only known for its accuracy of just +/- 10 seconds per year, it is also highly durable and resistant to shocks and magnetic fields.
It's very impressive this nine jewel watchmaker assembled watch, tuned by two different watchmakers and then ultimately it is a lifetime movement designed to last as long as you do. Also rather impressive is the fact that the 9F which originated in the early 1990s remains the best in the business featuring a number of refinements that you might not even notice at first glance, such as the latch adjustment system that ensures the second hand always lands precisely on the indices, moreover the hands are long, they have a full volume that extends to the tracks that they indicate. All this is achieved with a double pulse double torque motor system so that instead of having to use spindly under sized hands generally associated with quartz movements Grand Seiko can have these beautiful full sized and full-featured hand-finished seconds minute and hour hands, that are exquisitely polished and beveled like no other watch to keep you staring at it for more than just the time.