Jaeger-LeCoultre Duomètre Chronograph Moon dial Watch Review
The Jaeger-LeCoultre Duomètre Chronograph Moon, a bewitching timepiece featuring a copper-toned dial and housed in a platinum case, was one of the standout models of Watches & Wonders 2024. Angus Davies, a self-confessed fan of the Maison’s ‘Dual-Wing’ mechanism provides a detailed insight into what makes this product of the Vallée de Joux worthy of the term ‘Haute Horlogerie’.
Watches & Wonders 2024
From afar, a saloon race car, circumnavigating a track, can often resemble its road-going counterpart; however, in reality, it will be very different. Survey the race car’s interior and you will see it is sparsely appointed; just one seat, a roll cage and a fire extinguisher. Everything is optimised to deliver performance.
If said car is fitted with four seats, electric windows, air conditioning, regular glass windows and a bass-thumping stereo, it may prove a more congenial place to be, but its capacity for speed has been diminished. Quite simply, adding features undermines the raison d’être for creating a high-performance race car.
I was reminded of this situation while recently attending Watches & Wonders 2024. Allow me to elaborate.
Jaeger-LeCoultre has more than 1400 different calibres
Jaeger-LeCoultre, the esteemed Manufacture located in the Vallée de Joux, has always been at the vanguard of watchmaking, having created ‘more than 1400 different calibres’ and registering over 430 patents.
Back in 2007, the Maison unveiled its patented Duomètre mechanism. Recognising that adding complications to a watch can impair its chronometric performance, the inventive minds in Le Sentier conceived a very clever solution.
Jaeger-LeCoultre Duomètre mechanism (2007)
A watch fitted with one barrel should serve the escapement with a regular supply of power. If this power, or force, is plotted on a graph (with time shown on the x-axis), the line should appear horizontal. This indicates the movement proffers rate stability. If the watch is fitted with a chronograph, actuating the mechanism will often cause the amplitude of the balance to drop, impairing rate stability and, by default, precision.
In 2007, the Swiss marque conceived its so-called ‘Dual-Wing’ mechanism to counter such problems. A simple way of describing the system is to think of it as two discrete watch mechanisms, each with its own barrel and gear train, connected by a common regulating organ. One wing is dedicated to the escapement, used for accurately displaying the prevailing time, while the other wing is dedicated to powering the complications.
In reality, this means that actuating the model’s chronograph mechanism (or any other complication) will have no adverse effect on the model’s timekeeping prowess. Returning to the race car analogy, this is effectively like having all of the creature comforts of a luxury car without impairing its championship-winning performance.
At Watches & Wonders 2024, the historic Manufacture released a new iteration of its Duomètre concept, the Jaeger-LeCoultre Duomètre Chronograph Moon. This new model delivers extraordinary chronometric performance and is blessed with a pulchritudinous appearance. Moreover, its execution encompasses a plethora of considered details.
Jaeger-LeCoultre Duomètre Chronograph Moon dial
The Jaeger-LeCoultre Duomètre Chronograph Moon is a new creation, offered in two variants, a pink gold option and, my favourite, a platinum model sporting a copper-toned dial. Indeed, it is this latter variant that I have chosen to focus upon hereafter; however, other than the case material and dial hue, both models are virtually identical.
Image – Jaeger-LeCoultre Duomètre Chronograph Moon in pink gold (ref Q622252J)
Imbued with a high quotient of technical virtuosity, it seems perhaps a tad superficial for me to focus solely on the complexion of the dial. However, I feel compelled to mention the rich, autumnal tint of the model’s display. Quite simply, it is glorious and serves to differentiate the watch from many of its rivals.
The dial is a three-counter design and, at first glance, appears complex. However, do not fret, within a few seconds of making the JLC’s acquaintance, everything becomes clear. The prevailing time is shown on the subdial positioned adjacent to 10 o’clock, indicated using lancine-style hands. Short batons and Arabic numerals, positioned at the cardinal points, denote the hours. An aperture in the upper region of the subdial reveals a poetic representation of the day or night. The hour track sits upon a snailed surface while the centre of the subdial is endowed with an opaline finish.
A second subdial, located opposite at 2 o’clock, hosts three indications: a minute counter, an hour counter and a moon phase display. By locating two chronograph registers in one place, Jaeger-LeCoultre has mitigated clutter, augmenting lucidity. Occupying the same amount of dial estate, employing the same lancine-style hands and incorporating a similar snailed track, the Swiss brand has endowed the dial with a welcome degree of balance.
A flying seconds display (seconde foudroyante) is located on the third subdial, positioned above 6 o’clock. This indication performs a captivating dance, advancing in ⅙-second steps as it pivots on its axis. A flamboyant member of the chronograph dance troupe, it joins the aforementioned hour and minute counters to indicate elapsed time.
The status of each mainspring is indicated with two supremely-fine blued hands, one at 5 o’clock and a second at 7 o’clock. Two coaxially mounted, svelte hands measure the elapsed seconds (blue hand) and indicate running seconds (silver hand). The fine profile of these hands aids legibility and adds a high quotient of elegance. A tachymeter scale frames the dial, allowing the wearer to calculate the speed of an object over a known distance.
Throughout its history, Jaeger-LeCoultre has been known as a movement specialist. Indeed, over the years, the firm has supplied Audemars Piguet, Cartier, Patek Philippe and Vacheron Constantin. It remains a horological powerhouse and therefore it seems fitting that the dial of the Duomètre Chronograph Moon affords glimpses of the Calibre 391 within.
Jaeger-LeCoultre Duomètre Chronograph Moon case
As previously mentioned, the Jaeger-LeCoultre Duomètre Chronograph Moon is available in a choice of two noble metals: pink gold or platinum. This latter material exhibits a whitish sheen, differentiating it from stainless steel. Moreover, this dense precious metal proffers a reassuring heft that conveys a sense of value, while its neutral tone proves the perfect foil for the rich copper dial hues.
Back in 2012, I recall salivating over the Duomètre à Chronographe. Measuring 42.5 mm in diameter and executed in 18-carat pink gold, the model was, and remains, wonderfully handsome. Indeed, I often peruse the web, hoping to snaffle a pre-owned example.
However, the new Jaeger-LeCoultre Duomètre Chronograph Moon looks more contemporary with its convex crystal and arcing caseband. In fact, the Maison describes the new model as a contemporary take on the traditional savonette pocket watch ‘created by the Maison in the 19th-century’. The term ‘savonette’ means ‘a small disc of soap with rounded contours that can be cradled by the hand’. During Watches & Wonders, I was able to appraise its form at close quarters. Its near-organic shape reminded me of a beach pebble, eroded by lapping waters over many years and smoothed with the repeated kissing of coarse sand and adjacent stones. The resultant look and feel of the case is devoid of sharpness, bestowing a gentle mien.
The Jaeger-LeCoultre Duomètre Chronograph Moon measures 42 mm in diameter, the same as the aforementioned Duomètre à Chronographe (reference 6012420). However, the new watch looks much smaller than its angular forebear. I suspect this can be attributed to the glazing, the slimmer bezel and the new model’s gently arcing profile. When I canvassed opinions at the Geneva fair, inviting fellow journalists to share their thoughts, their comments merely served to reinforce my own opinion. Put simply, the new case looks neater and is more refined while the dial seems more expansive and easier to read.
Jaeger-LeCoultre has tastefully juxtaposed brushed and polished surfaces on this latest creation, upholding the approach employed on the Duomètre à Chronographe of yesteryear. However, in this instance, the firm has equipped the watch with new sophisticated lugs. These are discrete from the main case, allowing the brand to endow them with multiple finishes before attaching them to the main body of the watch with screws. These intricately formed lugs feature both brushed and polished surfaces and include microblasted recesses. This combination of finishes masterfully plays with depth, light and texture to confer a sumptuous aesthetic.
To the rear of the watch, an exhibition caseback affords sight of the hand-wound Jaeger-LeCoultre Calibre 391.
Jaeger-LeCoultre Calibre 391
In addition to having the impressive ‘Dual-Wing’ mechanism, the Jaeger-LeCoultre Calibre 391 is blessed with ultra-refined finishing worthy of the term ‘Haute Horlogerie’. The mainplate is embellished with perlage, the wheels are circular-grained, while the bridges are bevelled and polished to a resplendent gleam. While many watch movements feature bridges appointed with Côtes de Genève in the customary parallel stripe pattern, JLC has opted for Côtes de Genève rayonnantes, comprising rays that appear to emanate from the balance. The silvery hues of the beautiful bridges are punctuated with rubies and thermally blued screws, both of which reside within polished sinks.
The movement is regulated with a variable-inertia balance, a system that is superior to the index-regulated balance found on many mechanical watches. The main benefit of the variable-inertia balance is that the balance can be set more precisely. Moreover, should the watch be subject to a shock, it is less likely to require remedial regulation.
Jaeger-LeCoultre has subscribed to the traditional approach of affixing timing screws to the rim of the balance wheel. This creates more air turbulence than fixing inertia weights on the spokes of the balance wheel in-board. Personally, I prefer the latter approach as it heightens precision; however, I appreciate that some purists adore this traditional means of adjusting the moment of inertia. Nevertheless, setting aside this personal inertia-weight-fetishism, there is no question that the Calibre 391 is a technical tour de force that promises superb chronometric performance.
Jaeger-LeCoultre Duomètre Chronograph Moon – closing remarks
At Watches & Wonders 2024, some brands appeared cautious, releasing ‘animations’ of existing models. Set against this circumspect response to the challenges the industry is facing in some markets, Jaeger-LeCoultre has been refreshingly bold and ambitious. The Maison released four Duomètre references, including the Duomètre Quantieme Lunaire, two versions of this model (pink gold or platinum) and the mindblowing Duomètre Heliotourbillon. This latter, highly complex model is ‘a new tourbillon construction: one that rotates on three axis’.
I applaud the Swiss marque for its courage when many brands have chosen to ‘play it safe’. Based on my observations, the Jaeger-LeCoultre Duomètre Chronograph Moon deserves to succeed. As stated previously, it is like a race car having all of the creature comforts of a luxury limousine whilst still delivering championship-winning performance. Quite simply, this watch is destined to stand on the top step of the podium.
Further reading
https://www.jaeger-lecoultre.com/
Technical specification
- Model: Jaeger-LeCoultre Duomètre Chronograph Moon
- Reference: Q622656J
- Case: platinum, diameter 42.5 mm, height 14.2 mm, water resistance 5 ATM (50 m), sapphire crystal to front and exhibition caseback
- Functions: hours, minutes, seconds: chronograph with 12-hour counter, 60-minute counter, ⅙-second counter, central chronograph seconds; Moon phases, Night & Day, two power reserve indicators
- Movement: Calibre 391, hand-wound movement, frequency 21,600 vph (3 Hz), contains 54 jewels, two barrels, 482 components power reserve 50 hours
- Strap: alligator strap with small scale alligator lining with platinum pin buckle
- Price on application