Even though so much time has passed since its launch in 2006, the Breguet Classique Double Tourbillon remains one of the most complex and unusual double tourbillon watches on the market. Its fundamental construction significantly differs from traditional double tourbillons that are linked by a differential. It aims to provide greater transmission efficiency while delivering the same effect of a single, equalised and more precise rate. In addition, both wheel trains and tourbillons are mounted on a rotating plate that completes one revolution every 12 hours, which could be considered, in a broad sense, a tourbillon in itself. This configuration also allows the upper bridge of the tourbillons to serve as the hour hand of the watch.

In 2020, Breguet unveiled the Classique Double Tourbillon Quai De l’Horloge 5345, the first open-dial version, which lent itself to more elaborate artisanal decoration. It featured a platinum case and was named after the historic street in Paris where the original Breguet workshop was located. Today, the brand has introduced a striking rose gold model that has been decorated with hand-guilloché on the rotating plate, freehand engraving on the bridge plate, along with an abundance of anglage and internal angles. It all makes for a highly compelling watch that is both ingenious in its movement construction and very traditional in the amount of classical watchmaking craft it offers.

Extravagant, ingenious mechanics

Due to the nature of the movement, the Classique Double Tourbillon Quai de l’Horloge 5345 is a very imposing watch, measuring 46 mm wide and 16.8 mm in height, including its box sapphire crystal. In contrast to the majority of double tourbillon watches, whereby the differential is located along the gear train before it branches off in two separate directions, the calibre 588N2 has two complete sets of wheel trains. The planetary differential forms part of the hand-winding mechanism and is designed to distribute power equally to the two barrel ratchets when the watch is wound. At the same time, it regulates the rotational speeds of the barrels based on the mean speed of the two regulating systems and transmits this output directly to the time display – the rotating support and the minute pinion. If one barrel tries to unwind faster, the differential adjusts by transferring torque, which balances the energy levels between the barrels.

The purpose of this configuration is to improve transmission efficiency and ensure a stable flow of power to the escapement. This is because, unlike a traditional double tourbillon setup, the differential is not used to distribute torque stored in the mainspring to the regulating systems but only to move the display forward at the mean speed of the regulating systems. At the same time, a differential comprises numerous parts, including a carrier, entry and exit wheels, and satellite gears, which increases inertia along the gear train. Fluctuations in power delivery might occur if a single gear train were used initially.

With each barrel driving its own one-minute tourbillon and the differential gears balancing the power, this reduces stress on individual components, resulting in more efficient and reliable operation.

The movement comprises an astonishing 740 components, slightly surpassing the count of the triple-complication Lange Datograph Perpetual Tourbillon, to put it into perspective. The entire construction is intriguingly convoluted. The wheels visible under the full bridge at the back of the watch are actually part of the time-setting train. The hand-winding mechanism, along with the differential, are located above it on the dial side of the main plate while the rotating plate, which carries the wheel train and tourbillons, rotates on a large ball bearing in the main plate. Power reserve is 60 hours and the balances have a traditional frequency of 2.5Hz, which gives you a sense of the size of these components.

This theatrical, celebratory approach to mechanics has been pursued by numerous companies since the Ulysse Nardin Freak emerged as a pioneering example in the high-mech genre in 2001. This sort of out-of-the-box, high-risk watchmaking is often accompanied by aggressively futuristic styling, especially within the realm of double tourbillons and differential watches. But Breguet, however, combines its inventiveness with all the classic codes of traditional watchmaking. It has a fluted case band, Breguet hands, along with a solid gold movement that shows off a plethora of traditional finishing techniques.

Extravagant showcase of craft

The incredible degree of hand-finishing puts a spotlight on the sheer complexity and uniqueness of the movement. The rotating plate is made of rose gold and is decorated with a new radiant flinqué guilloché pattern specially developed for this watch. Breguet remains one of the few brands that specialises in traditional engine-turning. Today, it boasts a collection of 30 guilloché lathes, encompassing both rose and straight-line engines. Some of these lathes are centuries old, acquired at auctions or from private individuals, while others are replicas made by the manufacture.

The fixed mainplate is partially visible beneath the rotating plate. It is made of rhodium-plated gold and has also been engine-turned with the same wave-like pattern. The mainspring barrels are open-worked and supported by elaborately finished gold bridges that form the shape of a Breguet “B”. The anglage is particularly prominent with numerous sharp, internal angles while the jewels sit in deep, polished countersinks.

The wheel trains are laid out symmetrically on the rotating plate around the snailed differential bridge. There’s a pair of intermediate winding wheels that are held in place by small open-worked bridges. The steel tourbillon bridge and cages are black-polished with bevelled edges and bowl-shaped countersinks for the pivot jewels. Each balance wheel is equipped with a Breguet overcoil hairspring.

The blued minute hand, along with the partially blued upper tourbillon bridge that serves as the hour hand, indicate the time against a sapphire chapter ring engraved with Roman numerals and a minute track, both filled with blue lacquer.

With all the action on the dial side, the back of the watch was always going to be more subdued. However, the bridge plate, along with the island bridges, have been hand-engraved with an aerial view of A-L. Breguet’s workshop at 39 Quai de l’Horloge in the 19th century. The level of detailing is very impressive, from the texture of the roofs to the horse-drawn carriages in bas-relief on Pont au Change. To mimic the effect of shading, grey contrasts were created using a combination of black and white rhodium plating, enhancing the depth and visual impact of the engravings.

The small island bridges offers a glimpse of the gold-coloured wheels in the time-setting train. One of the intermediate wheels is supported by an elegant, open-worked bridge that lends itself to more anglage. The multiple mirror-polished screwheads and locating pins add a touch of contrast to the predominantly matte texture.

Given its dimensions, over-the-top mechanics, and price tag, the watch was obviously never intended to be an unobtrusive daily companion, but a spectacular showpiece. It’s rare enough that a watch offers a seamless integration of mechanics and aesthetics, tradition and innovation, but this is an exercise in a kind of radical ingenuity that’s harder and harder to come by today. Even after years and decades have passed since the introduction of the movement, the concept still remains incredibly compelling and the new Classique Double Tourbillon Quai de l’Horloge 5345 is a model that plays a serious game in just about every aspect of modern fine watchmaking.

Tech Specs: Classique Double Tourbillon Quai de L’horloge 5345BR/1S/5XU

Movement: Manually wound calibre 588N2; 60-hour power reserve; 18,000 vph, or 2.5 Hz
Functions: Hours and minutes
Case: 46mm by 16.8mm; 18K rose gold case
Dial: Sapphire chapter ring with Roman numerals and minutes track engraved and filled with blue varnish
Availability: Limited production
Price: Upon request