SEIKO Prospex Marinemaster Professional Spring Drive SBDB011 GMT – A Good Tool Watch With Some Quality Control Issues, A Review (plus Video)

You have guessed by now that I am a dive watch freak. One of my favorite dive watch brands is the Seiko Prospex series. Under this series, I have watches with water rating either at 200 meters, 300 meters or 1,000 meters. However, I do not have in the collection a Seiko Prospex diver with an intermediate water rating of 600 meters. Currently, Seiko has two sub-models with 600 meters water rating; the SBDB011 and the SBDB013. Both this sub-models uses the innovative Spring Drive movement by Seiko.

I decided to go for the SBDB011 to complete the set as it has a number of extras that the SBDB013 do not have. The first is the all-titanium construction including bracelet and second is the GMT complication. With this piece in hand, I would just about complete my collection of bracelet Prospex Marinemaster divers (there are still a few more to go but slowly but surely). Picking the winner is the simplest act, what came next was much harder.

The SBDB011 is a fully made in Japan (or JDM) model. It is the replacement model for the SBDB001 which was first launched back in 2005. Launched on 8 August 2015, the SBDB011 has a number of improvements over its predecessor. The new changes will be highlighted later in the review.



The ability to source a specimen in Malaysia is very difficult indeed. In Japan, it has a MSRP of YEN470,000 (inclusive of the 8% would be YEN507,600). The Seiko importer for Malaysia, Thong Sia, has set a price of RM19,716 (inclusive of 6% GST) for the watch which, based on a conversion rate as at 15 September 2016, was equivalent to YEN487,709. Looking at the price difference (we should compare the less tax price in Japan as exporting it out of Japan allows us to claim back the 8% from the Japanese Government against the local GST inclusive price), it would be more economical to source it from Japan. It would be very unlikely that Malaysian authorized dealers with their brick-and-mortar shops could offer better discounts than the internet based merchants from Japan.



The SBDB011 has been called the Seiko Marinemaster GMT as it is the only Marinemaster in the current lineup that has a GMT function. Like all Marinemasters, this watch continues the tradition of a tool watch: imposing, spectacular and practical while at the same time, reflecting an evergreen iconic design that would live forever.

The watch is made out of a special titanium alloy with a special DiaShield protective coating to protect the surface against common impacts or scratches. The DiaShield protective coating is new and was not available in the previous SBDB001 model. The same material and coating is also used for the bracelet. It has a diameter of 46 mm excluding the crown with a thickness of 17 mm. Its lug-to-lug length is 55.9 mm. Despite the size, the weight is a mere 174 grams due to the extensive use of titanium.

The glass covering the dial is sapphire crystal with anti-reflective and anti-fogging protection. It is thick enough to easily handle 600 meters of water pressure. Meanwhile, the opposite side is a solid titanium screw-down case-back.

Another physical feature of the watch is the crown located at the 4 o’clock position. A large screw-down crown, it has fine gear-like edge to facilitate grip. The top surface has the “X” image stamped on it. This is the Prospex logo that Seiko have started to incorporate on all the models under this series. This is unlike the SBDB001 which has the “S” image stamped on it. Meanwhile, the bezel has large ratchet tooth edge. Unidirectional and with a solid 120 click increments for a full rotation.



The most contentious physical feature of the watch is the lugs. The lugs are measured 21 mm across which should already start the alert bells ringing for prospective buyers. There are also two Allen or Hex screws, one near each lug to facilitate removal of the bracelet. In a nutshell, the concept that Seiko adopted for the SBDB011 is a clamp system. Due to this unique feature, it is difficult to replace the bracelet with third party straps. I personally do not have a problem with this system. I prefer all my watches to be stock and I very seldom indulge in replacing original bracelets or straps unless it is unavoidable. Even then, I would try to search for an original replacement to make the watch stock again.

The watch also has three other complications. The first is the date aperture at the 3 o’clock position. Unfortunately, this date aperture has substituted the lumed marker in that position. In my opinion, this causes an unbalance to the dial symmetry which I cannot appreciate. At least Seiko decided to use a black Arabic numbering over a white background to supplement the missing lumed marker. The second complication is the power reserve indicator located at the 8 o’clock position but closer to the center of the dial. The scale is a quarter circle where the scale stars from zero power at the North position and full when the needle points West (turning counterclockwise). The third complication is the GMT function represented by the all white GMT hand. The 24 hour GMT scale is located on the chapter slope with Arabic and line markers.



The dial is black and well below at some distance away from the sapphire glass surface. The sloping chapter ring is high and the bottom half of it is printed with the 24 hour GMT scale while the upper half is painted black. There are hour markers for every hour except for 3 o’clock where a date aperture is present. There are five lines of text on the dial. Only the brand name is printed on the upper portion of the dial whereas the lines with words “PROFESSIONAL”, “600 m” and “Spring Drive” are located on the bottom half of the dial. The fifth line of text is located around the peripheral of dial which consists of the words “JAPAN” as well as some manufacturing codes. All the texts are of different font and sizes which does not overwhelm or clutter the dial surface.

This watch has five hands. The GMT and Power Reserve hands are like rapier swords, the hours and minutes hands are like Roman short-swords whereas the seconds hand is like a foil sword. The Power Reserve hand is polished without any paint. The seconds hands is also similar apart from the ball weight which is painted with LumiBrite paint. The GMT hand is fully painted in white. The hours and minutes hands are painted with Lumibrite with edges left bare.

Contrary to the LumiBrite paint used in the SBDB001, the latest recipe enhancement to the LumiBrite paint has been touted by Seiko to glow up to 60% longer than previous versions.



The bracelet comes standard with a ratcheting diver extension system, flip-lock clasp with push-button release and large links. This bracelet design in new and is more angular than the typical bracelets used by Seiko. The links have polished and brush pieces which makes it very sophisticated. There are no half links but there are 4 micro-adjustment points on the clasp itself to facilitate good resizing.



The SBDB011 uses the Spring Drive movement Caliber 5R66. This particular movement uses 30 jewels and has a main spring barrel sufficient to power up the watch for 72 hours. It has an accuracy of +/- 15 seconds per month. The number of parts needed to make one 5R66 is 276 components. This movement is similar to the one used in Grand Seikos, the 9R66, except for finishing (not as refined) on the rotor bridge and the shape of the rotor itself.



This automatic movement can be wound manually. Due to the GMT function, the hours hand can be adjusted on its own. Pulling the crown into the first position allows one to make that change. The date function is not a quick-set system. One would need to turn the hours hand to make the change. Meanwhile, pulling the crown into the second (and last) position allows one to adjust the GMT and minute hands. At this position, the seconds hand would stop moving (hacking).

This engine is made at Shinshu Watch Studio in Seiko Epson's facility in Shiojiri, Japan. This technology uses an electro magnetically controlled regulation of the mainsprings. The conventional escapement is replaced with a device that Seiko calls a Tri-synchro Regulator to regulate the unwinding of the mainspring. The regulator controls the use of the three forms of energy used in the Spring Drive mechanism; the mechanical power of the mainspring, the electrical energy generated from this mechanical power, and the electromagnetic energy that governs the rotation of the glide wheel. The energy produced by the glide wheel is used to power a control circuit and quartz crystal oscillator, which in turn regulates the electro-mechanical braking of the glide wheel. The glide wheel's speed is sampled 8 times per second and compared with the reference quartz signal by the circuit which operates at 32,768 Hertz. A variable braking force is continuously applied to regulate the glide wheel's frequency. This is the only movement with a time-only feedback (or phase-locked) loop in existence today.

The Tri-synchro Regulator's innovations result in a watch where the hands glide instead of ticking as in a conventional mechanical or quartz watch. This is because the movement never stops as in a traditional escapement; it is slowed to the proper speed by the brake. Below is the manual for the 5R66.

SEIKO 5R66 and 5R67 Manual on Scribd

The SBDB011 casing and movement component are also designed to provide a magnetic resistance of up to 4800 A/m (or 60 Gauss), similar to the standards required by JIS (Japanese Industrial Standard) Class 1 or DIN 8309 (Deutsche Industrie Norm; German Industry Norm).

Above is a photo of the illumination generated by the watch while in the dark.

Unfortunately, my iPhone 5 was not able to catch the brilliance of the illumination coming out of the new LumiBrite paint. In reality, the light pops out brightly that allows you to even seen the other aspects of the watch that does not have the paint.



The Wearing Experience

Below is a short resume of the three Marinemasters for reference.

SBDX001	SBDB011	SBEX001
• 300 meters WR • Caliber 28,800VPH 8L35 • Weighs in at 210 gm • 44 mm by 14.6 mm	• 600 meters WR • Caliber SD 5R66 • Weighs in at 174 gm • 45 mm by 17 mm	• 1000 meters WR • Caliber 36,000VPH 8L55 • Weighs in at 199 gm • 48.2 mm by 19.7 mm

The SBDB011 is a seriously capable saturation diving watch designed for professionals. From a dimension and water rating points of view, the SBDB011 fits in-between the iconic Prospex Marinemaster 300m SBDX001 and the newer Prospex Marinemaster 1000m Hi-Beat SBEX001. However, from a weight perspective, the SBDB011 is the lightest of the three Marinemasters. This factor makes it a better wear in my opinion.



The slippery surface of the watch (thanks to the DiaShield protective coating) coupled with the angle façade of the watch casing allows it to easily slip under cuffs. To me, this is an important test as it makes the watch practical in formal attire. Honestly, I don’t dive and even swimming is an event that is not often done. My watches are primarily worn in an office or formal setting.

The GMT function is very useful function. In my line of work, I sometimes travel and it would be good to be able to keep track of my home time. By allowing users to independently adjust the hours hand, it is easier to manage the GMT function. The availability of the bezel even allows a third time zone to be tracked.



The watch is comfortable on the wrist. The information on the dial is easily readable although there could be some confusion between the GMT hand and the minutes hand since both are generally painted white (normal white paint and white LumiBrite paint). Most GMT watches have their GMT hands to be unique compared to the other hands either by shape or colour. Seiko decided to just subtly make small changes to the shape of the GMT hand. A quick glance may not allow one to automatically differentiate between the two. However, after a while, you’ll get used to it.

As highlight earlier, the unique lug system used for the SBDB011 makes it extremely difficult to use third party straps. Some modification would be required to fit the special clamps near the lugs. Those of you that love to ‘accessorize’, this watch may not be the one for you. Below is the video of the watch on my wrist.




The Reveal

The watch comes in dark blue watch box (plus a packaging sleeve of the same colour) that is made in Japan. The manual and guarantee documents are slotted inside the packaging sleeve. The watch box only has the watch plus the pillow which it rests on in the center of the box.



The packaging sleeve has the following dimensions: 16 cm long by 12.5 cm wide and 10 cm tall. The main watch box has the same length and width as the packaging sleeve, but with a height of just 8 cm tall.


Quality Control

In this last section, I would like to comment on quality control. I was actually surprised to see the paint job on the LumiBrite was not as good as I would have expected. Looking closely at the hour markers, I can see the consistency was not balanced and on one of the marker, the lume overshot the boundary ever so slightly (note the 9 o'clock and 11 o'clock markers).



I hope Seiko note this feedback seriously. A brand that has been built for 100 years can easily unravel due to quality control issues. It may be permissible for the cheaper Seiko 5s but for a professional Prospex model, at this price point, it is unacceptable.


Photo Gallery

SBDB011	SBDB011	SBDB011