A mid-range industrial watch: the Longines Spirit Zulu Time 1925 [Wearing Review]

The Longines Spirit Zulu Time 1925 will be released in 2025, marking 100 years since the birth of Longines' first dual-time watch. Watch writer and watch enthusiast Shun Horiuchi will provide a detailed review of this new model, describing it as a "top-quality industrial product" and an "impeccably excellent watch" from the perspective of an "industrial" watch, a term he coined himself.

Review of the Longines Spirit Zulu Time 1925

　In my impressions in March of this year, I arbitrarily proposed the term "industrial" watch, and praised Omega's "Constration" as the ultimate in this field (article:http://www.webchronos.net/features/132793/The Longines Spirit Zulu Time 1925 is a masterpiece that inevitably evokes the height of this "industrial" watch.

　This is what I thought strongly about the Longines Spirit Zulu Time 1925. It's flawless in every aspect, from the exterior to the functionality and precision, and its high level of perfection clearly demonstrates the power of the huge capital of the Swatch Group. This watch, which even gives off the impression of "the violence of capital," is truly an excellent example that I would recommend to anyone. The design, details, and above all, the packaging are so excellent that I wanted to own one myself.

　This is a special model celebrating the 100th anniversary of Longines' first dual time wristwatch, which displayed a second time zone.

　The current Longines Spirit Zulu Time has been available since 2022 and is available in 42mm and 39mm case sizes. There are several variations in size and dial, including a titanium case. While all models are based on solid case backs, the Longines Spirit Zulu Time 1925 is unique in that it is the first to feature a sapphire crystal case back.

Light-conscious design and details

　The design itself is likely to fall into the category of likes and dislikes, but I would still like to discuss the parts that left the strongest impression.

The ingenuity of the dial

　First of all, there's the matte black dial. At first glance, it's so jet black that it seems to absorb all light. The Longines "Winged Hourglass" on the dial, the five stars that give the Zulu Time its distinctive character, and even the applied Arabic numerals that stand out are all rose gold in color, with the white areas made of luminous paint. There's a date window at 6 o'clock, and the base of the white numerals that stand out is the same matte black as the dial. Despite the design not making the date window stand out, the date itself is very easy to read, and the functionality and appearance are highly integrated. Even though I don't think a date is necessary, I think it's a good idea to have one on this watch.

　Outside the Arabic numerals are small diamond-shaped luminous indices that blend into the minute track. The tip of the second hand also has a diamond-shaped luminous indices, which fly over these diamond-shaped indices. I thought the continuity of this design was excellent. The hour and minute hands are pencil hands with beautiful luminous paint.

　Of particular note is the GMT hand. The rose gold tip is painted matte black up to the middle, giving the impression that only the tip is raised. The minute track around the outer edge of the dial is raised by a step, and this step is a thin rose gold-colored mirror finish. When light is shone on the indexes and hands from the front, this part sinks into the dial without making much of an impression, but when viewed at an angle, it reflects light and asserts its presence. The matte black dial controls which parts are reflected by the light depending on the angle, so it is never garish, nor too plain.

　This raised minute track also has the effect of reducing the height of the dial faceplate. GMT watches with four hands that sprout from the center have a high distance from the dial to the top-most second hand, which makes the faceplate thicker and tends to look cheap. While it may be possible to reduce the distance between the hands on higher-end watches, it's difficult to do so at this price point.

　This model solves this problem with the presence of a minute track that is raised one level. The hand located at the bottom is a short hour hand that can rotate inside the minute track. The GMT hand, minute hand, and second hand are all long enough to reach the outer edge of the dial, and these three rotate on the minute track. This structure seems to keep the height of the faceplate to just the height of three hands, which I think is a very clever solution.

　All 11 Arabic numerals except for the 6 are perfectly flush, and the four rose gold-colored hands stand out beautifully against the matte black dial. Try using a light source to reflect light off them. The rose gold-colored parts that stand out against the jet-black dial are very attractive, and you'll see how effective this light-controlling design is. The effect is a success.

　The outer periphery of the dial is fitted with a 24-hour bezel that can rotate in both directions. The inner ring is made of 18K rose gold GC and has a subtle circular brushed finish that is not too flashy and is well-finished. The bezel itself is likely pressed, and the surface is nicely polished, with no roughness between the knurling and a uniform texture.

The case is a true "industrial" design.

　Of particular note is the quality of the case. It is right in the middle of the "industrial" style (which I would arbitrarily propose), and appears to have been precisely machined using a CNC machine, with the top and edges of the lugs and the sides of the case having an extremely fine satin finish. This is not a hairline finish, but rather appears to have been achieved using a CNC grinding machine. Generally, grinding results in an intricate satin texture on the surface, but it is a processing method used to achieve highly accurate dimensions and shapes, and is different from polishing, which is used to smooth out surface textures. This is often confused, but please note that the mechanical engineering implications are different.

　What I found to be an excellent aspect of the case design is that the corners of the lugs have been given a large C shape, creating a mirror finish. As a result, this mirror finish effectively separates the case sides from the lugs, successfully giving the entire case a unique look. The satin-polished surface looks so sharp right down to the edges, so it's possible that this mirror finish was also machine-cut and achieved without any finishing. It would certainly be dulled if buffed.

　The underside of the lug appears to have a typical circumferential sawn edge, but it is precise and uniform, clearly indicating that it was finished with sharp tools.

　This case demonstrates the power of modern multi-axis CNC machines, making it a top-quality industrial product. Its finish is so high-quality that it barely feels hand-finished, thanks to the elimination of a large proportion of the manual processes. "Hand-finished or machine-finished" is no longer a question of whether one is better than the other, as they are polar opposites. However, even with superhuman hand-finishing by a master craftsman, it would be extremely difficult to produce such a large number of cases with the same level of precision. This case has reached that level.

　The case back is made of sapphire crystal and is secured with six screws. While sapphire crystal glass generally makes a watch thicker, the stainless steel case back itself is thin and has a low height. When viewed from the side, the sapphire crystal glass surface actually protrudes slightly from the case back, which has a positive effect on the wearing comfort. However, watches with screw-fastened case backs generally tend to collect dust due to sweat, so it is best to clean them frequently. We often hear about problems with screws breaking in this area of ​​watches over time.

　The crown is tapered at the base and has a long shape that makes it easy to operate. The surface of the crown is sandblasted, and the embossed "two-winged hourglass" is polished, creating a contrast and a luxurious feel. It is likely that the entire surface is matte when it is stamped out, and the embossed "two-winged hourglass" is polished later, but this too may be a one-time finish. I recall that the crown of the Omega Constration, which I previously reviewed, also had a similar finish. It may be that it is delivered by the same supplier within the Swatch Group.

The bracelet also shows the "light-conscious design"

　The bracelet is conveniently detachable from the watch body with one touch. Its high rigidity is also ensured by the high precision of the machining of the solid flush fit parts, which have protrusions that fit onto the side of the bracelet side of the case.

　The bracelet is three-link, reminiscent of a Rolex Oyster, but the mirrored finish on both ends of the center links makes it look like an Omega at first glance, making it a basic design. However, this model expresses this by polishing the mirrored surface with a stepped edge, and the points where the left and right links meet the center link are tapered and then polished, a finish unique to Longines.

　When you look at the bracelet from the front, the polished parts on both ends of the center link reflect light, and when you look at it diagonally, the tapered parts of the left and right links reflect light, which is another design element that I felt was taken into consideration when designing. The intricacy of the satin is of course great, and the overall finish has a very high quality feel.

　The bracelet's thickness is appropriate for the thickness and weight of the head, and it tapers toward the buckle. The buckle's fastening mechanism is easy to operate and has a solid design, with the left and right push buttons having a mirrored surface that contrasts strikingly with the satin buckle side. The buckle itself is made by bending a plate, but the ridge where the top and sides meet appears to have been carved with a large C, and the polished finish gives it a texture that is hard to believe is made from a bent plate, making it a well-designed and well-crafted piece.

Design and details summary

　I have written extensively about the details, but to sum up, 1) the design seems to have been carefully considered with light in mind, and 2) the case and bracelet have a very high-quality texture thanks to the advanced machining process used to finish them. These factors make this a very attractive watch.

How about the movement and accuracy?

　The movement used in this watch is the Cal. L844.4, an automatic movement made exclusively for Longines by ETA SA. Its unusual frequency of 25,200 vibrations per hour, or 7 vibrations per second, is likely the optimal solution for the approximately 72-hour power reserve and escapement, including the mainspring and silicon balance spring.

　The automatic winding rotor, etched with a world map, is rose gold in color, creating a sense of unity and luxury. The movement's barrel bridge and balance cock are each individually and completely decorated with relatively large circular graining. I think this level of finish is impressive for this price range. It also features a free-sprung balance, with weights on the four arms that appear to be for rate adjustment.

　This movement is chronometer-certified by COSC, so high precision is expected. The watch used for the impressions was worn for eight consecutive days, then taken off while sleeping and measured by changing the position of the watch, such as on the dial or on the crown. It achieved an astonishing accuracy of +6 seconds in cumulative error. And the progress did not vary from day to day. The standard deviation was extremely small, with a daily accumulation of just a few tenths of a second.

　Another major advantage is that it has a power reserve of approximately 72 hours, meaning it won't stop even if you don't wear it for two days over the weekend, and it's also anti-magnetic, which I felt was extremely well-made, similar to the Omega Constellation mentioned above. Although I have some reservations about silicon balance springs, achieving such high performance in this price range, and being part of the huge conglomerate that is the Swatch Group, I think there are few concerns about future parts supplies, so I felt it was a perfect choice.

　There is no longer any complaint about its performance, and upon reflection, I realized that of the many watches I own, the only one that could rival this watch in accuracy was the Jaeger-LeCoultre E168 Geophysic, which I had just received after returning from Le Sentier. The fact that this is mass-produced as a mid-range wristwatch is truly amazing.

Wearing impressions

　The first thing I noticed when I saw this watch was the beautiful contrast between the jet black dial and the rose gold. Then, upon closer inspection, I was blown away by the quality of the craftsmanship of each piece, as I mentioned earlier.

　The bracelet was pre-adjusted, so it fit perfectly on my wrist, and I immediately began trying it out after setting the time. When I fastened the buckle, I noticed that the bracelet was quite tapered. It narrowed from the 21mm lug width to a mere 16mm at the buckle. This design is in line with recent trends, as the tapered width gives a more dressy impression, but the bracelet itself is made of solid links and is quite thick, and the buckle is also quite substantial. While the edges of each part of the bracelet felt quite sharp, they were not aggressive to the skin and I never felt any discomfort. The buckle was easy to fasten and remove, and it never came off accidentally.

　The thickness of the case, or head, is 13.5mm, which is the same as the solid-back model in the same series. The case back has been carefully crafted to be thin, which is highly commendable. However, since I wore it during a week of scorching heat, the sapphire crystal case back stuck to my wrist with sweat. This is unavoidable. Personally, I prefer the feel of a solid-back, especially in the summer, but I can understand the desire to see the movement inside.

　The 24-hour bezel has a pleasant click to it, making it easy to turn it without any reason. The ease of use of the GMT function is particularly noteworthy, as the hour hand can be easily adjusted in one-hour increments. Surprisingly, the date also moves back in sync, giving you peace of mind knowing that this design won't break.

　Overall, this is a very easy-to-use watch, and with its magnetic resistance and high accuracy, it can be said to be extremely excellent for everyday use today.

Finally, my thoughts on the watch packaging

　I believe that a package is not just a collection of details. The idea is that the watch you want to make comes first, and the details are determined in the process of realizing it. Therefore, while the design and level of finish will naturally vary depending on the brand and price range, they should naturally be determined by each brand's identity and resources. When you look at watches from this perspective, you can say that a watch with an excellent package is consistent and well-balanced. This is something that made me feel strongly about the Longines Spirit Zulu Time 1925.

　Excellent details are a given in this price class today, and it makes me think that the only thing left to discuss is the packaging. If I were to be asked to write an impression of an "industrial" watch like this again in the future, I would of course write about the details, but I even felt a certain apprehension that it would end up being a discussion of the packaging and how it functions as a watch. This is an excellent watch with no flaws whatsoever, and one that I would recommend to anyone.