Seiko dive replica watches are known as being some of the best, most reliable divers out there, and it is for due cause. The SKX line (commonly known as the “monster”) and the watch I’m reviewing today – the Seiko Marinemaster SBDB009 “Spring Drive Tuna” are a couple of the most well-known dive replica watches out there, period.
To put 600 meters into perspective, consider the recreational limit for scuba diving — a veritable “kiddie pool” at a paltry 30 meters. Then consider Ahmed Gabr’s world record scuba dive to 332 meters in 2014, marking the deepest a man has ever been with tanks strapped to his back. All depths considered, the 600 meter water resistance of the 6159-7010 (better known as Seiko’s “godfather” Tuna) is pretty damned deep, far beyond the depths where humans were ever intended to go without the assistance of submersibles. Nowadays, we have “deep diver” replica watches that go a whole hell of a lot deeper, but building a professional-grade dive watch that could survive that kind of pressure in 1975 was a pretty incredible feat of engineering. (That’s probably why it took Seiko a full decade to introduce the Tuna, after breaking into the dive watch market in 1965 with the legendary 6217 150m diver.)
Based on direct feedback from professional divers, it’s the uniqueness of that engineering which drives the quirky design language of the Tuna; namely its distinctive, can-shaped shroud, designed to repel side impacts and protect the watch’s case, crown, and bezel at crushing depths, and inherently lending the watch its nickname.
So, in keeping with the traditions of the godfather, we have the fully realized Seiko Marinemaster SBDB009 (aka: the “Spring Drive Tuna”); a 600m titanium dive replica watch at the apex of four decades of dive watch tradition. Granted, it shares the same depth maximum as other “mainstream” luxury divers like the Planet Ocean from Omega. However, what sets the Tuna apart is a healthy dose of classic Japanese tinkering and innovation, and a ballsy experiment conducted earlier this year when Seiko strapped two of its Tuna models (the automatic SBDX011 and the quartz-powered SBBN013, respectively) to the exterior of a special submersible for a joyride off the Asian continental shelf (see above video).
The purpose? Dive until they stopped working. And “stop working” they both did — the quartz at 3,000 meters (nearly 10,000 feet) and the automatic at a staggering 4299 meters — four times beyond the watch’s claimed depth rating. The aim was not to measure failure, but to inspire confidence that the engineering in Seiko’s Prospex series is capable of feats well beyond what’s advertised on the dial.
Largely unchanged in spirit from its grandfather 6159, the ultra-modern Seiko Marinemaster SBDB009 Spring Drive Tuna rules the roost across some 40 years of Seiko’s shrouded Tuna editions. [For those wondering, the recently released SBDB013 North America edition is identical to the 009 being reviewed, save for the model number and the “X” etched in the crown, delineating its entry to the Prospex collection.]
And while this Tuna doesn’t carry the deepest depth rating — that honor belongs to the 1000 meter options like the quartz-powered SBBN013 – rest assured it’s still the cream of the crop, featuring a “high intensity” titanium inner and outer case, anti-glare treated sapphire glass, Seiko’s spellbindingly smooth 5R65 Spring Drive movement, and a few other modern embellishments we’ll visit in a moment.
To fully appreciate the Tuna, one must look past its well-fed exterior and embrace it for adhering to the traditions of purpose-built utility. Yes, it’s ugly. But no detail here is superfluous, including the polarizing case shroud — a distinct engineering solution demanded by commercial divers in the late sixties. And when you examine the Tuna as the sum of its cleverly engineered parts, you’ll discover what makes the watch so damned endearing: its character.
But arguably, the best part of this particular Seiko Marinemaster SBDB009 Spring Drive Tuna comes from within — the 5R65 is mechanically identical to the 9R65, though it’s fitted to this fake watch without much of the ultra high-end hand finishing signature to everything that comes out of Grand Seiko’s Morioka studio (which is where this watch is built), and is accurate to within 15 seconds per month.
How? Well, think of Spring Drive as sort of a hybrid automatic movement, which takes the best of both quartz and mechanical movement worlds to achieve its insane accuracy, lengthy 72-hour power reserve, and that signature stutter-free sweeping seconds hand. Now, movement purists or retro grouches might want to tune out here, but Seiko accomplishes this by removing all the regulating elements from what would otherwise be in an automatic movement and replaces them with a single regulator, which takes kinetic energy drawn from the mainspring and turns it into electrical energy, which in turn keeps the quartz crystal continually charged. Think of it almost like a pedal-assist bicycle, jumping to life at the slightest movement and running smoothly for great lengths on end, though virtually indistinguishable from the outside.
At first glance, everything about the Seiko Marinemaster SBDB009 Spring Drive Tuna appears pretty standard in the realm of dive replica watches. Matte-black dial, high-contrast circular luminous indices, broad arrow/sword handset, and a traditional 120-click diver’s bezel. But like any great Seiko, the sum of its parts is most often appreciated with a second (or third) glance, or under the scrutiny of a loupe.
Perhaps the three most impressive elements in the watch’s execution are all part of its finishing, starting with that inky, “Black Ion” DLC coating. Vertically brushed on the outer walls of the shroud, and polished to a mirror along the cutouts and topmost ridge, it’s astonishing to find this much contrast and texture in what is basically an entirely black replica watch. The bezel insert is also polished to a mirrored sheen, providing an additional layer of texture and contrast to top it all off. The Seiko Marinemaster SBDB009 Spring Drive Tuna is visually stunning — an exercise in very sharp, measured contrasts, which many will appreciate. Granted, it’s hardly menacing, but it’s a layer of finishing complexity that’s rarely seen in just the color black.
The dial and hands on the Seiko Marinemaster SBDB009 Spring Drive Tuna have largely escaped major changes since the watch’s introduction 40 years ago. For longtime Tuna fans, the most recent changes to a bold arrow hour hand and a sword minute hand haven’t been met with universal appreciation, though it could be argued that the aesthetic found in the Seiko Marinemaster SBDB009 Spring Drive Tuna revision is a little cleaner and more modern, with fewer shapes and intersecting lines competing for attention on the dial. Beyond that, many of the watch’s core signatures remain intact, including its brilliant luminosity. Seiko has stated the Seiko Marinemaster SBDB009 Spring Drive Tuna is using a new proprietary formula of LumiBrite, yielding brighter and longer burn times — an awfully impressive claim, especially considering the brightness of previous generation Seiko divers.
The dial itself is laid out nicely, starting with a steeply sloped chapter ring which terminates in a flat rehaut wherein each generously filled hour marker is painted. As awesome as this looks, applied indices on matte black or matching DLC posts would add a greater degree of depth and take this dial to the next level. The applied “Seiko” wordmark at 12:00 is also great touch, nicely contrasting the printed text at 6:00. It’s worth mentioning that four lines of text can be too much, but when watch-specific terminology is kept brief, and multiple fonts and sizes are used, it’s a pleasure to behold. Not naming names here, but a number of *ahem* Swiss brands could greatly benefit from a lesson in typography.
At 9:00, you’ll find another signature of the Spring Drive movement within: the power reserve. Love it or hate it, the indicator actually proves quite useful with a diver, while providing real-time feedback that the Spring Drive movement is something entirely different from a traditional automatic movement. With the gauge at front and center, you’ll notice how ridiculously efficient the movement really is — from quickly winding up to full juice, to slowly meting out its 72 hours of reserve power (more than enough to allow it to lay dormant for a long weekend), this is a watch that rarely takes a break — even when you do, it takes a great deal of effort to get it to stop running.
Fans demanding more of a tactile experience with their replica watches uk will appreciate the 120-click, uni-directional bezel, which glides around the inner perimeter of the protective shroud with extremely smooth, satisfying precision. Gripping the deep ridges at 2:00 and 8:00 between the protective shroud’s cutout with even wet fingers is hardly an issue, and rotating the bezel still feels as though you’re turning the dial on a finely tuned combination lock to open a vault. The bezel’s glossy ceramic inlay is capped at 12:00 with an intensely luminous triangle that perfectly matches the tone and brightness of the lume within the dial itself.
Obviously, the shrouded case design will always be the Tuna’s most polarizing element in terms of both size and wearability, but it’s ultimately what makes the watch such a conversation piece, and a joy to wear.
The shroud is also guilty of greatly increasing the watch’s measurements on paper, however, the Seiko Marinemaster SBDB009 Spring Drive Tuna is unique in that it wears significantly smaller — and lighter (thanks to that titanium construction) than its intimidating 50mm (excluding the crown) case measurements belie. The dial and bezel together are only 41mm wide, but even more important, is how the strap is fixed to the lower flange on the shroud, rather than to lugs on the case itself (like the 1000 meter Tunas). This clever “lugless” design (measuring a reasonable 46mm from bar to bar) prevents the strap from being pinched outward at the wrist, enabling the watch to sit naturally flush, and more comfortably against the wrist. The 18mm thickness will probably be a hangup for some, but if you’re interested in wearing a Tuna with a suit or sleeved shirt, you’ll quickly find that Seiko makes no apologies for a watch whose dimensions have changed little since its commercial diving days in the ’70s.
The included silicone/rubber B-22 strap might appear familiar for those with bad memories of Seiko’s stock Z-22 strap (a painfully stiff rubber OEM strap included on many Seiko divers), however, the strap is yet another upgrade Seiko has made to the Prospex line. Super pliable, breathable, and – most importantly — comfortable, the strap finally feels worthy of the watch it is attached to — something many Seiko fans haven’t been able to say for quite some time.
However, as great as this strap is, you’ll inevitably want to enjoy the Seiko Marinemaster SBDB009 Spring Drive Tuna’s impressive versatility on a wide variety of straps, but to do this, you’ll have to first do battle with the fat, shoulderless springbars that the watch ships with. And if you’ve ever tried removing shoulderless bars without drilled lugs, it’s a process only slightly easier than removing one’s own appendix. In fact, I’d probably rather give myself an appendectomy using only a springbar tool, than have to change these damn things again. Thankfully, a quick trip on “the Bay” revealed a bevy of double-flanged options in both wide and standard diameters, ensuring the pain of this procedure was a one-time affair.
Even with its pseudo-luxury trappings, the Seiko Marinemaster SBDB009 Spring Drive Tuna will never be an everyday watch, or the starring role in a “one-watch” collection (if there even is such a thing), as it lacks the versatility of other classic deep divers like the Sea Dweller, Planet Ocean, or the Sub from DOXA. However, it more than makes up for this shortcoming by doubling down on personality that’s as much fun to look at and wear as it is to talk about. It’s sort of like a Mercedes G-Wagon: always a little out of place, but never unwelcome — unless, of course, you plan on taking it directly into the context it was actually designed for.
But context aside, there’s one more thing about the Seiko Marinemaster SBDB009 Spring Drive Tuna that no amount of reading or photo-ogling will prepare you for: this watch is black. Very black. Make no mistake — it’s not black in a stealthy, “tactical pedestrian” sort of way, nor does it make any attempt to fly under the radar; it’s black in a sinister, soul-stealing sort of way — one whose sharp contrasts and mirrored finish give off such impressive depth, it draws the eyes in and threatens to swallow up anyone who stares a little too long. With a price of $160, the Seiko Marinemaster SBDB009 Spring Drive Tuna watch has a lot to offer potential buyers.