Thursday, August 6, 2015

Seiko Perspex Marinemaster 1000m Hi-Beat SBEX001G Titanium Limited Edition (or SBEX001) - A true showcase of Seiko’s 50th year in the dive watch field, A Review

When Seiko introduced the Seiko Perspex Marinemaster 1000m Hi-Beat SBEX001G Titanium Limited Edition piece in March 2015 during Baselworld2015, I was mesmerized. A lot of innovative features were incorporated into this watch. Although its dimensions appear very formidable, I immediately got the 'have-to-have-it' feeling.

Key specifications of the watch are as follows: The watch face has a diameter measuring 48.2 mm (excluding crown). The watch case has a thickness of 19.7 mm. Made out from a single piece of titanium block, access to the internals only via the front of the watch. The machinery is the top-of-the-line Hi-Beat movement from Seiko. Water rating at 1,000 meters without the need of a helium escape valve mechanism. More details about all these later.

Since its introduction back in March 2015, I have been patiently waiting for Seiko to commence delivery. The watch is finally available for purchase. Unfortunately, there is a catch to this watch. For all its infinite wisdom, Seiko decided to make it a limited edition piece with a production run of just 700 specimens. This means the price would be a premium and very scarce to find.

Sure enough the listed price in Japan was set at YEN650,000 or EUR6,400 or USD6,850.
Nevertheless, all is not lost, I do have a number of channels that I can tap to get the best deal possible. By pure luck, my resourceful agent from a local Seiko authorized dealer happened to note that five pieces have been allocated to Malaysia and his shop will be given two. I immediately commit to buy at a very special price (this is a beauty of maintaining a consistent relationship with a good dealer).

Shape wise, the SBEX001G is similar to the 300 Marinemaster. It has a monocoque case i.e. the insides can only be accessed via one major opening – in this case via the dial side. The screw-down crown is located at the 4 o’clock position. There is a date window and time is shown via a three hand system. Apart from these similarities, the two watches are effective different like night and day.

The first major difference is size. As highlighted earlier, this watch is big, very big. At 48.2 mm (excluding crown) across and at a height of 19.7 mm, the first assumption is that not everyone can carry this watch with confidence. However, on closer inspection of the watch, there are a few design features that effectively improve the wearing experience. The monocoque case design allows Seiko’s designers to curve the bottom part of the watch to sit properly on one’s wrist (more like ‘wrap’ around). Despite its size, in my opinion, it wears like a 42 mm watch. Nevertheless, the height of the watch is still something that would be difficult to muster if you want to use the watch with formal wear.

The second major difference is the main material used. Instead of stainless steel, Seiko opted for a special proprietary titanium alloy nicknamed Bright Titanium to keep the piece lightweight and coated in a proprietary coating called Diashield, to improve scratch resistance. The bracelet is also made with the same material and protective coating. Every time I pick up the watch, I am always surprised by the disconnect between size and weight. The weight of the SBEX001G is just 199 grams.

The third major difference is the movement. It is equipped with Hi-Beat 36000 Caliber 8L55 which until now only exclusively used for Grand Seiko watches. The Caliber 8L55 runs at 36,000 vibrations per hour (or beats per hour; bph) or 10 beats per second. Although not as elaborately decorated as those set into Grand Seiko watches, the efficiency of the movement is similar. The movement is assembled by hand at the Shizukuishi Watch Studio in Morioka, Japan. The power reserve is 55 hours which is impressive considering all that power comes from just one mainspring barrel.

Before we start the review, let us appreciate the history behind the concept of Seiko’s dive watches.
This year, 2015 marks the 50th year that Seiko has been manufacturing dive watches. Throughout the 50 years, Seiko has been recording a number of firsts. Below is a graphical time on the achievements of Seiko on just this product line. More details on the milestones can be found here:

Since my watch collection hobby started fairly recently (in relative terms to Seiko dive watch history) I have yet to have in my collection any of the watches in the list although I do have the famous Emperor Tuna and the 300 Marinemaster. Hopefully, this watch would make it into the list.

The SBEX001G is a model under the Prospex class of watches. These are professional line of watches composed of models intended for professional activities and sports (e.g. dive watches, chronometers, running watches, flight watches, etc.). The name is a play on the words Professional Specifications, hence Prospex. The design specification meant that this watch is capable of withstanding abuse without missing a beat. In another word, made like a tank. Despite its ‘rough-and-tumble’ specification, the built is like a sports car. Polished using the Japanese art of Zaratsu, or blade polishing technique (used to create Samurai swords), the finishing applied gives a mirror quality that belies its tool-like attributes.

When I got my watch from the dealer, I note the size of the watch box. It is much larger than the typical box assigned to Prospex dive watches. Also, the traditional yellow strips synonymous with Prospex line is missing from the box. I suspect this departure is due to the fact that this is a special limited edition watch.

The package comes in two main sections. The first is the outer box with consist of a dark grey cardboard box with the “SEIKO” brand printed in silver at the top. Taking the top off revealed a black wooden box which is the main watch box. On this box the “Seiko” brand as well as the line brand “PROSPEX” plus logo are prominently printed in white at the top.

The first dark grey box is not just a protective covering for the main watch box. It also serves the purpose of storing the manual as well as the guarantee document for the watch in a small sleeve at the edge.

The main wooden watch box hinges at the back and open to reveal the watch on a watch pillow in the centre of the box. The inside of the box is covered by grey cloth covering. On the inner top of the watch box, printed in gold, is the “50th Anniversary Seiko Dive Watch” logo.

Apart from the watch and pillow, you will also find a standard Seiko silicon compound strap. I have written on this strap in the review of the Seiko SRP653K1. This is by far, the most comfortable diving strap I have ever had the pleasure to experience. There is also a rather simple white piece of paper to indicate where to find the strap in the watch box which is totally out of style. I suspect this was done as an afterthought in view of many inquiries from buyers of previous watches that comes with extra straps; “Where is the extra strap?”.

The first obvious thing I love about the dial design is where the Seiko designers placed the date window. Finally, they heard my feedback on this. As you all know, I love symmetry and replacing one of the primary markers for a date window is a definite design flaw for me. For both the SBDX001 and SBDX011 watches, Seiko felt the 3 o’clock marker would be ‘better suited’ as a date window instead. I totally disagree with this assumption. By making the replacement, the character of the watch changes. Instead of making it ‘complete’, it now appears to be ‘missing’ something. The replacement of a primary marker with a date window caused the dial to look asymmetrical. This would not have been an issue if the primary marker was replaced with something of an equivalent ‘weight’. As it stands now, this mismatch creates a visual perception of instability.

Below are dial photos of my SBDX001 (left) and SBDX011 (right) watches. On comparison, the SBEX001G’s dial looks more balanced than the other two watches.

The markers, hands and wordings appear to be made out of yellow gold material or paint. Although nothing about gold was ever mentioned in other reviews, on closer inspection with a magnifying glass, there could be gold involve in the watch (at least in plated form). This could also be the reason why the watch commanded such a high price. It does have a subliminal shine to it.

The hands on the SBEX001G appear unique. The hour-hand has the shape of a Roman broadsword with a distinctive luminous paint pattern just before halfway up the hand until the end. The longer minute-hand has an obelisk-like design with a fat tail. The luminous paint is also applied just before halfway up the hand until the end. The second-hand is different. It is thin with a ball at the end of the hand. Only the ball part of the second-hand has luminous paint. The final third section of the hand is painted red.

All primary hour markers are painted with luminous paint. The shapes of the markers on the four corners of the compass are different with the 12 o’clock marker being most unique of all. It has a design more akin to the Seiko Sumo but with more curves. In fact, it looks like an upside down bell.

Meanwhile, the chapter ring is very steep like the side of a deep well. On it are minute markers also in golden paint.

There are seven line of text on the black dial. In the other previous Marinemasters, the distribution of text has been one above the center-line and the rest (or five lines) under the center-line. This time, Seiko decided to even it out (three above and four below the center-line). What is more interesting was the use of fonts. There are actually five different fonts used. One for the “SEIKO” brand (first line), one for both the “AUTOMATIC” (second line) and “MARINEMASTER” (fourth line) words, another for “HI-BEAT 36000” (third line), the fourth is for the word “PROFESSIONAL” (fifth line) and finally for the number “1000m” (sixth line). The seventh line of text is minutely small and sits at the very bottom with the words "JAPAN 8L55 -00A0 A 2". The word first two words on the seventh line signifies the production location and the movement used. The rest of the numbers is something that I cannot yet fathom (if anyone knows, please put up in the comments section at the end of this posting).

Some suggest the reason of using multiple fonts is to ensure difficulty in copying. Nevertheless, centering the words with a top-bottom alignment minimizes any possible visual oddity.

The bezel is a typical diver's bezel with a 120-click unidirectional full rotation and engraved with a combination of numbers and markers in a 60-minute scale. As required on all professional dive watches, a luminous triangle is provided at the 12 o'clock position. The outer-side of the bezel is gear-like in design for easy of gripping while wearing gloves.

From my observation, the titanium bezel appears to be coated with either a glossy black ceramic lacquer or ceramic inserts. It is so smooth to the touch and mirror-like. I could not find any information about the bezel apart from what I can observed (if any reader knows anything about the bezel, please leave a note at the end of this posting).

An interesting visual cue on the watch is the bolted-on-bracelet, secured by two screws on each end. The screwed on end-links serve to secure not just the bracelet, but also the bezel. It enhanced the rugged-look of the watch.

The watch has a water depth rating of 1,000 meters. The unique design employs a one piece bright titanium case that features an L-Shaped gasket to make it impermeable to helium and appropriate for saturation diving. The engineering is so precise and the manufacturing process is so exact that this watch does not need a helium escape valve system to operate at such depth. The crystal is a thick sapphire to ensure it does not crack under pressure and also utilizes an anti-fogging coating.

This design also affords the internal movement some anti-magnetic protection. In this case, up to 16,000 A/m (or 200 Gauss).

The large screw-down crown has the Prospex logo sand blasted onto it. Even though the watch is an extreme diver, there is no outward appearance of any additional strengthening needed to withstand 1,000 meters of water pressure. This goes to show the quality of the product specifications and production processes. All that is needed is already designed within the casing.

The main lugs have straight pass-through holes to assist strap or bracelet replacement. Meanwhile, the end-links measures 22 mm across. The titanium bracelet then tapers down to 18 mm at the clasps. From the photos above, based on the location of the link-pins, it would appear that this is a new bracelet design from Seiko.

In the photos above, you can also see the curvature of the watch casing to follow the shape of a wrist. This design goes a long way towards making the watch more wearable despite the size. Instead of just sitting on the wrist, the watch wraps itself on the wrist, making it more stable. Moreover, the side walls are not flat but angled and this helps minimize the possibility of snagging on shirt cuffs etc.

The back (there is no case-back) has the famous “Tsunami” logo of Seiko divers. Apart from the standard information expected behind any production watch, there is a symbol of the Titanium compound used as well as a symbol of its anti-magnetic protection capability. This watch has a serial number of 260 out of 700. Honestly, I half expected a much more intricate back pattern considering this is a limited edition piece to celebrate an important milestone in Seiko's watch making journey.

The clasp is fold over with push button release. For a professional diver with a bracelet, Seiko provides an in-house ratcheting divers extension mechanism within the clasp. This system is similar to the one on my Seiko 300 Marinemaster but made out of Titanium instead. It easily adjusts in and out to give a maximum 1 inch and a bit additional length to the bracelet. Above are pictures of it before extension and after extension.

A lot of people have written about the quality of the luminous paint used by Seiko. Using their own proprietary paint formula called LumiBrite, the latest recipe enhancement has been touted by Seiko to glow up to 60% longer then previous versions.

On the right is a picture of the luminescence generated by the LumiBrite paint on the SBEX001G. While my iPhone5 camera struggled to focus on the dark regions on the watch, the luminescence was so bright that everything close to any LumiBrite painted area can clearly be seen. Mind you, the paint was only charged for approximately 20 seconds using a halogen table-lamp.

I read with interest in watch review articles as well as watch forums the quick rejection by many commentators of the SBEX001G purely because of the dimensions. I must admit, initial, I did have the same misgivings. However, my logical thinking kicks in to slowly justify the misgivings away.

This is the 50th anniversary of Seiko’s foray into the professional dive watch space. I bet the design team given the task to create an iconic watch to befit this momentous milestone has everything under the Seiko Group at their disposal. The choices made were well thought-out and brought into a package that does justice to the 50th Anniversary milestone.

The base reference for the Prospex Marinemaster Professional Limited Edition SBEX001G was the Seiko diver watch Reference 6159-7001 launched in 1968. Capable of diving down to 300 meters, it was powered by the 6159A ‘hi-beat’ movement, the 25 jewel, 36,000 bph masterpiece. Mind you, in 1968, a watch that could dive down to 300 meters was considered top of the range. In the 21st century, the level commonly deemed for ‘top of the range’ professional dive watches is around the 1,000 meter mark. Hence, Seiko decided to make this level as part of the specification for the SBEX001G. As for the choice of movement, back then (in the 1960s), there was a race to create a 36,000bph movement. Girard Perregaux was the first to create a 36,000 bph movement 1966. Within a year, in 1967, Seiko created their very first Hi-Beat caliber – the hand-wound 5740C. What better way to showcase capability then to put in Seiko’s latest Hi-Beat movement, the 8L55 (effectively the 9S85, minus the level of decoration and regulation required under the Grand Seiko quality control requirements) into the SBEX001G.

While on the subject of making the SBEX001G special, why not also make it have anti-magnetic capabilities and use Titanium to make the whole package light (Titanium is also an excellent metal for dive watches due to its ability to withstand the corrosive seawater much better than stainless steel).

So, how does it wear?

Surprisingly well for a large watch. The use of the lightweight Titanium and the curved casing contribute immensely to its wearing comfort. In the series of photos above, I had the opportunity to wear the watch with formal wear in the office. Despite the perception that you cannot wear a cuff shirt with the SBEX001G, in reality, you actually can without any issue of snagging. The angled sides help the watch to easily slip below shirt cuffs.

The Hi-Beat caliber makes the movement of the second-hand smooth and mesmerizing. Compared to typical speeds of common calibers (such as Seiko 4R36 and ETA 2892) in the 21,600 bph to 28,800 bph range, the movement of the 8L55, as reflected by the second-hand, is superior (still can’t beat a SpringDrive movement though). As I have been wearing this watch for just a couple of days, I can’t comment much about the accuracy although I doubt it would be poorer than the factory guaranteed accuracy of +15 seconds or -10 seconds per day.

Overall pleased with this watch. It has the wrist presence and a slew of the best technologies Seiko can muster at this point in time. A true showcase of Seiko’s 50th year in the dive watch field.


Additional Notes:

The official price of the watch in Kuala Lumpur is put at staggering RM27,060 (including GST). However, if you get to know the dealers, you can get at a price similar or better than internet merchants.

There is also an additional bonus that you would not get from internet merchants. You may also get some free gifts. In my case I got two very nice pens from Longines and Raymond Weil.


DRIVING SYSTEM Automatic with manual winding mechanism
CALIBER NUMBER 8L55: 37 jewels, 36,000 vibrations per hour and has a power reserve of 55 hours
CASE/BAND Titanium with super hard coating; 22 mm lug width
GLASS MATERIAL Sapphire Crystal
GLASS COATING Anti-fogging Coating
WATER RESISTANCE 1000m Saturation Diver
CASE DIAMETER/HEIGHT 48.2 mm; 19.7 mm
WEIGHT 199 grams
FEATURES Hi-Beat 36000;
Hand-winding capability;
Power reserve approximately 55 hours;
36,000 vibrations per hour;
Rotating Bezel;
Screw-down Crown;
Three-fold clasp with push button release with secure lock and slide adjuster;
A black extra-strength silicone strap is included;
Limited Edition of 700 pieces.

User Manual of SBEX001G

Photo Gallery


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  2. I own # 388. Delighted with this watch. Curious to know how many winds would you apply to crown from completely wound down?
    I occasionally apply 5 if I have not worn the watch overnight. I would not want to damage the watch. Nowhere have I seen any data on this question.

    1. Hi,
      Generally 20 turns should be fine when the watch is completely dead. SEIKO has a special disengage clutch on the winding stem that would kick in when the main springs are totally wound up. This protect it from over stressing the springs. I was made to understand if you wind slightly over 40 turns you should hit the limit. Not to worry as the clutch will not allow you to spoil the watch by over winding anyway.


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