De Bethune : DB28TIS8

Let’s make one thing absolutely clear from the start: even if this DB28TIS8 were to feature a traditional case, it would nonetheless be well worthy to appear in this column. But Denis Flageollet, the brand’s co-founder and “technical brain”, has in fact dreamed up a highly innovative case radiating a decidedly contemporary aesthetic. The movement is housed within an apparently standard 43 mm-diameter “container”. Apparently is the operative word, however, since it is in fact neither round nor cylindrical. A distinctive protruding section at 6 o’clock provides a generous opening revealing the famous spherical moon, while the crown is strategically positioned at 12 o’clock. The purpose of this manoeuver was to free up the 9 – 3 o’clock axis in order to secure there the pivoting points of the floating lugs (available in two different lengths !!!). The slender, openworked latter elements are subtly cambered to follow the curve of the wrist. As implied by the TI letters in the reference number, the entire case is made from grade 5 titanium. The choice of this alloy enables a perfect polished finish, ensures the robustness of the construction and particularly the mobile parts, and contributes to the exceptional comfort of the watch thanks to its incredible lightness. The smoothly accessible and easy-grip crown is screw-locked. There is no dial as such on this timepiece, but instead a silver disc bearing the chapter ring and evoking the finest horological traditions.

Just as with the watch exterior, the hand-wound DB Calibre 2115 embodies the finest execution and finishing with a modern architecture and technical innovations that ensure reliable rating and improve its timing qualities. The energy is supplied by two auto-compensating barrels for which a patent has been filed and which supply extremely constant force throughout the power reserve. The user can witness this reality thanks to the torque indicator placed along the same axis as the entry barrel between 2 and 3 o’clock. A discreet marker moves between a sapphire (meaning optimal torque) and a ruby (minimal torque) in order to provide this precious piece of information – complemented by an indicator of the power reserve (announced at six days) appear‑ing through a window in the caseback. The symmetry of the movement designed with inverted hand-fitting leaves plenty of space for the silicon/platinum balance and spring assembly ensuring optimal inertia thanks to the combination of these two metals. The bridges and mainplate are adorned with vertical Côtes de Genève and black galvanic plating, while the chapter ring bridge serving as a dial creates a striking contrast thanks to its mirror polish. The balance is secured by the spectacular famous triple pare-choc which supply absorbs all impacts. As for the balance-spring, it features the famous flat terminal curve from a brand that was one of the pioneers in the use of silicon for balance-springs, thereby guaranteeing exemplary isochronism. Finally, the moon plays a starring role at 6 o’clock ! The famous spherical indicator provides a luxurious and comfortable reading of the age of the moon and naturally attracts the interest of all those fortunate enough to have seen this watch at close quarters.
De Bethune’s extremely limited production quantities (around 250 watches per year) leave little opportunity for handing over this type of timepiece to a third party for a testing bench operation. Nonetheless, thanks to the work of the brand’s teams, we were entrusted with a prototype that had already been worn over a certain period of time. The rates were measured in the fully-wound state and then after 24 hours of running. The power reserve in this case turned out to be six days and six hours. On the chrono-comparer machine, the balance-and-spring assembly displayed its undeniable efficiency. The amplitudes and the rates measured are textbook chronometry material. Whatever the degree of winding, the amplitudes in the horizontal position ranged from 280° to 290°, and from 270° and 275° in vertical positions. The rates fell within the +3 sec./day to +10 sec./day range in all six positions, with a 6 sec./day delta in the fully-wound state and 7 sec./day after 24 hours of running. Winding and time-setting were extremely smooth, and in terms of comfort on the wrist, it’s hard to imagine anything better.

In the opinion of this writer, Denis Flageollet is probably one of the best watchmakers of the 20th and 21st centuries. He knows how to develop, produce and finish movements according to the strictest criteria. He also knows exactly which issues in mechanical horology still require improvement, and is excellent at finding original and effective solutions. Moreover, he accomplishes all this in an open-minded and innovative manner, demonstrating a humble attitude equally only by his authentic talent – a  genuine delight in the world of ego-rology. This mind-set is clearly perceptible in the timepieces themselves, which are their own best advertisement. In a nutshell, the Geneva Watchmaking Grand Prix Golden Hand award is well deserved and symbolically rewards the work accomplished by the De Bethune teams since the creation of the brand.

Cet horloger chevronné analyse une montre qu'il porte pendant toute une semaine et en livre son bilan technique et esthétique

Review overview