Grand Seiko SBGA105

Spring Drive cal. 9R15

Factory Spec. 10 SPM

In my pursuit of a collection that includes an example of every good, affordable escapement and significant horological development, how could I not own a Spring Drive? And in my pursuit of accuracy, how could I not own the limited edition 9R15 version?

Ordinary Spring Drives are rated to 15 SPM. The 9R15 is rated to 10 SPM.


The technology inside is pretty impressive. It really is. I get it. I do. Honestly. I saved up and I bought it. But after wearing it for a couple of hours I realised that I just don't love it. In fact I don't love it to such an extent that I'm putting it up for sale. I have never sold a watch, before, except those that had been purchased specifically for resale. That's the extent to which I don't love this watch.

So what's wrong with it? Nothing, really. Take a x30 loupe and compare the SBGA105 to a comparably priced Rolex (say, the 214270) and you will see that the finishing on the Grand Seiko is absolutely astounding in comparison to the rather utilitarian factory finish of the Rolex. Don't get me wrong, the Rolex is beautiful and it is on my 'wish list' of watches to buy. But the Grand Seiko is a work of real craftsmanship. Made if FAR fewer numbers than the Rolex, every Grand Seiko Spring Drive is hand finished to astonishing levels for the price. Multi-faceted applied markers and hands; minute details in textures; traditional Japanese hand-polishing by renowned craftsmen... the list goes on. And while both the Rolex and the Grand Seiko boast complete 'manufacture' status, we could point out that Rolex don't make their own steel or jewels or shock absorbers. Of course not! you might say. That would be ridiculous! Well, Seiko do. Every single tiny little thing is made either directly in the Grand Seiko workshop or in another Seiko facility in a nearby town.

And what's not to love about the Spring Drive itself? Mechanical watch afficionados often wax lyrical about the smoothness of their second hand's sweep, and discuss how hand length and width and dial finish and beat rate can all affect the perception of smoothness. Well, the second hand on the Spring Drive glides more smoothly than any mechanical watch. It is continuously trying to spin around, driven by a mainspring, and is electromagnetically braked eight times per second in order to keep quartz-like time. So, unlike the frequent stops that a mechanical hand makes as it ticks up to ten times per second (in the case of a 36,000 hi-beat movement), the second hand on a Spring Drive never stops. Alongside the Seiko 5S21 and 5S42 (which use a dampening 'trick'), the Spring Drive produces the world's smoothest gliding second hand of all.

But that's the problem, really. It's an awful lot of money for something I cannot get used to. I'm a 'precision' sort of person, and I like to know exactly when a second has started and exactly when it has elapsed. Ordinary mechanical watches give me enough of a headache, as it is. When you're trying to set the time, you REALLY want to know that the second hand has stopped precisely at 12 o'clock. Tricky with an ordinary mechanical watch; nearly impossible with a Spring Drive. When you want to time a watch to very precise levels, you REALLY want to know when a second has started and when it has finished. High speed video photography and slow motion play back makes this possible for an ordinary mechanical watch, but it remains all but impossible for a Spring Drive. Not that you would ever need to time a mechanical watch with a high speed video, because you can just stick the thing on a cheap timegrapher. The Spring Drive is silent. Timegraphers don't work on it, so you have to use observation to try to time it.

And then, once you have spent an age trying to time it accurately and you have found it needs adjustment, what can you do? With an ordinary mechanical (even with a Rolex, if you were feeling brave), you could pop the back off and fiddle with the regulator. No such thing on a Spring Drive. Even your local watchmaker couldn't help you out with that one. You'd have to send it back to Seiko for a tune-up.

So, on the one hand I applaud the Seiko Spring Drive. It brings a higher level of accuracy to mechanical watches. Quartz accuracy without ever needing a battery. On the other hand I can't stand it for its imprecision. Yes, I said 'imprecision'! The deepest, truest core value of horology has always been to ever more accurately mark the passing of time. I grant you that the 'aesthetics' side of horology has been around for a long time, but it seems to me that only relatively recently have watchmakers said "ok, that's accurate enough. Now let's start adding value through new features". All those who work on the accuracy side of the game must, surely, somewhere deep down in their souls, die a little each time their work is undermined by an aesthetic decision. I mean, what is the point of having quartz-like accuracy if you put it in a watch with a smooth gliding second hand that cannot be read with any reasonable degree of precision? Adherents to the mechanical way don't really seem to mind the one or two seconds per day that their watches gain or lose. And they instinctively shun the Spring Drive for having a quartz crystal. Fans of high accuracy quartz wouldn't give two cents for the accuracy of a Spring Drive and they (if they're anything like me, at least) would positively shudder at the inability to judge the time PRECISELY.

There are, of course, those in the middle. Those who probably have a few fairly expensive quartz (probably dive watches) and mid-range mechanicals, and who love the idea of a mechanical and who would love their mechanicals to have quartz-like accuracy. And, well, yes, the list probably goes on. There are people who would love a Spring Drive. I thought I would, too. For me, however, while having a Spring Drive is still going to be an important part of my collection, I think I will sell the SBGA105 and wait maybe a decade or so until the prices of second hand Sping Drives on eBay have fallen a long way.

September 2015 update: Sold!

Some details for this watch may be missing because it has not been subjected to comprehensive testing.

Parent Company Seiko Holdings Corporation
Brand Grand Seiko
Model Series Historical Collection
Model Name Self-dater Spring Drive
Model Number SBGA105
Case Number 0AE0
Serial Number 331 / 500
Approx. Date of Manufacture 2014
Calibre (mvt maker) 9R15
Calibre (brand) 9R15
Factory SPY 10 SPM
TC Appproach none
Frequency (XO 1) 32 kHz
Frequency (XO 2) n/a
Rate Adjustment Factory
Major Inhibition Period n/a
Minor Inhibition Period n/a
Power Mainspring, automatic winding
Cell Number n/a
Case Back Screw
Water Resistance 10 bar
Features 3-hand, no numerals dial
  Power reserve indicator
  Date (not perpetual)
Timing Results Basic data  &  Further details
Images Photos - Large File Sizes!
Documents User manual