Jaeger-LeCoultre Duomètre à Chronographe mechanical white gold 42 mm Full Set 2011

A brief history

In 2007, Jaeger-LeCoultre continued to consolidate its position at the forefront of fine watchmaking. The resounding success of the Gyrotourbillon 1, the Master Minute Repeater and the Reverso Grande Complication à Triptyque, at the time the most complex wristwatch in the world, bore witness to the technical ingenuity of the Manufacture and reinforced its exceptional reputation in the field of horological complications.

That year, Jaeger-LeCoultre reached a new milestone with the launch of the Duomètre collection and the presentation of its first model, the Duomètre à Chronographe. This timepiece, with its style and technical sophistication, immediately positioned itself in the Haute Horlogerie segment.

A true micromechanical revolution, the Duomètre à Chronographe houses a new-generation movement, equipped with the original ‘Dual-Wing’ concept. This ingenious system has separated the watch's functions into two autonomous mechanisms: one dedicated to indicating the time and the other to additional functions, all with a single regulating organ in common. This innovation made it possible to achieve chronometer-worthy precision without compromising the use of a complication. With this calibre, its case with welded lugs and its grained dial, the Duomètre masterfully reinvented the great watchmaking classic: the chronograph!

Available in 5 different versions, we present here the rarest and one of the most desirable: the white gold version with a black dial, limited to 200 pieces!

Let's get acquainted

The Duomètre à Chronographe by Jaeger-LeCoultre is a watch that leaves no one indifferent. Its generously sized white gold case, 42 mm in diameter and almost 14 mm thick, is a testament to the watchmaking complexity it contains, while remaining reasonable for a dress watch. The straight, finely brushed caseband has a beautifully satin-finished appearance, while the welded lugs, polished like the bezel and the rim of the transparent back, emphasise and refine the silhouette of the watch. The whole exudes a discreet elegance, reinforced by the slightly retro touch provided by the single push-button.

This version has a slightly grained black dial with the timepiece's serial number on a plate at 6 o'clock. This dial offers exceptional readability and clarity despite the complexity of the functions on offer! A real challenge brilliantly met by Jaeger-LeCoultre! The dial is structured around two large symmetrical counters: the one at 10 o'clock displays the hours and minutes of the watch, while the one at 2 o'clock indicates the hours and minutes of the chronograph. Ingeniously, a window integrated into the chronograph counter reveals a disc displaying the minute units from 0 to 9, allowing a precise and instantaneous reading of the elapsed time. At a single glance, it is possible to visualise the measured hours and minutes, for example 2 hours and 6 minutes, without having to decipher the position of the minute hand.

Two power reserve indicators, located at 7 o'clock for the watch and at 5 o'clock for the chronograph, complete the information available on the dial. The jumping seconds hand, which moves in 1/6th of a second increments, is cleverly positioned at 6 o'clock, between the watch and chronograph counters.

To make it easier to read these multiple indications, the team of designers has introduced an intuitive colour code. The hour, minute and seconds hands and the power reserve indicator are rhodium-plated, while those of the chronograph (hours, minutes, seconds and jumping seconds) are gold. This colour coding makes it possible to instantly distinguish the functions of the watch from those of the chronograph, even when the indications are in motion.

The whole is dressed with a black alligator strap with a white gold folding clasp.

The 380 calibre: a watchmaking revolution

The art of measuring time has always fascinated mankind. In theory, a chronograph mechanism and its dial should offer perfect precision and reliability, allowing for repeated and continuous measurements without affecting the accuracy of the time display. However, in a classic chronograph, the mechanism is driven by the seconds wheel and draws its energy from the same mainspring as the time display. A clutch ensures the coupling and uncoupling of the chronograph, and although the vertical disc clutch minimises energy loss, it cannot completely eliminate variations in precision between operation with the chronograph engaged or disengaged. These variations, negligible for short measurements, become significant for longer periods.

With the unique concept of the ‘Dual-Wing’ Calibre applied to the chronograph, the use of a clutch becomes superfluous. The accuracy of the watch is therefore not influenced by the chronograph. The Duomètre à Chronographe can therefore be considered as the first chronometer watch with a complication. The construction principle of the calibre 380 uses a fascinating watchmaking mechanism to replace the clutch: the foudroyante. Mounted on the escape wheel axis, a second wheel with 30 teeth transmits the rhythm of the balance to a star with 6 teeth. The latter completes one rotation per second, and indicates 1/6th of a second by means of a hand at 6 o'clock. By means of a reduction gear, a kinematic chain then displays the chronograph seconds, minutes and hours. A finger activated by the column wheel stops the foudroyante star in an intermediate position that allows the teeth of the foudroyante escape wheel to pass without contact. When the chronograph is restarted, the finger is withdrawn and the torque provided by the chronograph barrel sets the star in rotation, which once again meshes with the wheel with 30 teeth. Both simple and subtle, this mechanism, produced in minute dimensions, requires precision components and exceptional watchmaking talents that only a manufacturer with expertise in all the trades is able to provide.

The split-second mechanism was used for the first time in pocket watches dating from the 19th century. At the time, the jumping seconds hand was directly driven by the watch's seconds wheel to indicate a fraction of a second. For this reason, the jumping seconds hand always continued to move without offering the possibility of being stopped or reset. The watchmakers at Jaeger-LeCoultre could not present a chronograph worthy of the name without the ability to reset the jumping seconds hand. For the 380 calibre, they developed a system that allows the jumping seconds hand to be reset at the same time as all the other chronograph counters.

As explained earlier, to ensure that the complication does not compromise the precision of time measurement, the ‘Dual Wing’ mechanism consists of two barrels and two independent gear trains – one for time measurement, the other for the complications – united by a single escapement. One gear train is thus entirely dedicated to the time function (hours, minutes, seconds), and the other to the chronograph function. Each mechanism is powered by its own barrel, ensuring a power reserve of 50 hours (50 hours for the time, 50 hours for the chronograph). There is no energy transfer between the two. A single crown is used to wind both barrels: clockwise to wind the time, anti-clockwise to wind the chronograph.

Although this calibre may appear complex at first glance, it quickly becomes intuitive to use. The chronograph mechanism can be easily activated, stopped and reset thanks to the monopusher at 2 o'clock. Each press of the button triggers a sequence: start, stop, reset, and so on.

This simple action orchestrates a fascinating mechanical ballet: the instantaneous starting, stopping and resetting of the chronograph hour and minute hands, the minute unit disc, the central seconds hand and the jumping seconds hand. The sight of these five elements simultaneously returning to zero is a striking horological experience.

With its remarkable finish and beauty, the Jaeger-LeCoultre Calibre 380 has a large balance wheel that beats at a frequency of 21,600 vibrations per hour. It can be admired through the watch's sapphire crystal case back. The independent barrels are snailed and hand-chamfered, while the ratchets are sunrayed with the words ‘chronograph’ and ‘hours and minutes’ engraved and gilded. The nickel silver bridges reflect the Dual-Wing concept, with taut, straight lines for the time mechanism and arabesques for the chronograph, revealing the hearts, hammers, jumpers, column wheel and wheels of this mechanism. A decoration inspired by the brand's great pocket watch tradition. The gears feature circular satin-finishing and hand-polished mouldings. The mobiles, also hand-chamfered or adorned with polished mouldings, are snailed or softened. Finally, the flame-blued steel screws underline the complexity of this exceptional calibre.

The package

This white gold Jaeger-LeCoultre Duomètre à Chronographe is an exceptional piece in very good condition! It comes as a ‘Full Set’, with its case and all of its original documents. We know this watch very well, as we sold it in April 2011 in our Lepage boutique in Rouen. This watch also underwent a full inspection at Jaeger-LeCoultre in March 2019, guaranteeing its authenticity and perfect functioning. Finally, for your peace of mind, this watch comes with a 1-year Lepage warranty.