The new Vacheron Constantin Les Cabinotiers Dual Moon is a one-of-a-kind dual-faced Grand Complication watch powered by a brand-new in-house movement with 11 complications.

This timepiece houses the new in-house Calibre 2755 TMRCCQP, which offers 11 horological complications including minute repeater, perpetual calendar, precision moon phases, sky chart and tourbillon.

The double moon phase display is the key feature of this grand complication watch in white gold. Often relegated to the background, the moon display is now very much in the forefront on this model, asserting its striking presence both by its colour code and by its size.

It offers a vision of the Earth’s satellite as it appears in the northern and southern hemispheres, the central moon phase indication, already a rarity in the watchmaking world, is therefore characterized by a double display. This complication, already featured in the Les Cabinotiers Tourbillon Armillary Perpetual Calendar – Planetaria watch, makes a strong statement in this highly technical grand complication.

Les Cabinotiers Dual Moon Grand Complication: Front Dial

The front dial features Off-centre mean solar time with hours and minutes, Precision moon phases and age in both hemispheres, Gregorian perpetual calendar with day, month, leap-year indications and instantaneous retrograde date hand.

This highly complex model is distinguished by the legibility of its hourly and astronomical functions.

On the front of the watch, the eye is drawn to the depiction of the moons in the two hemispheres on a disc coaxial with the central hands and shaped like a starry dome. Its deep blue colour makes a striking contrast with the silvery hue of the dial as it performs a complete rotation in 59 days, 12 hours and 45 minutes.

These astronomical moons respect the duration of the synodic months with a discrepancy of only 24 hours every 122 years and 16 days. The age of the Moon is indicated around a periphery scale graduated from 1 to 29½. On this titanium dome graced with rhodium- plated moons on a blue-sky background obtained by physical vapour deposition (PVD). The uneven surface of the moon, like the brilliance of the tiny stars, was achieved by diamond cutting.

The display of the hours and minutes of mean civil time complete with lunar cycles has been slightly off-centred upwards to enable the harmonious integration of calendar indications.

Instead of the traditional pointer-type dials used for perpetual calendar indications, this timepiece features rotating discs. The semi-instantaneous display of the day and the instantaneous display of the month and leap-year appear through apertures, as does the date display. Here again, this display positioned on the upper rim of the dial is shown through a semi-circular window, but with a retrograde hand.

The four-part dial construction and the finishing of each fully matches the technical nature of the model. A 0.35 mm thick sapphire dome is placed on a silver-toned metal baseplate with a sandblasted finish and openworked calendar apertures.

This dome beneath which the moon-phase disc turns is fitted with two ‘masks’ whose smoky appearance is achieved by metallisation. It is held in place by a curved brass ring, satin-brushed with an opaline varnish, which in turn bears the white gold hour-markers.

Les Cabinotiers Dual Moon Grand Complication: Back Dial

The back dial of this Les Cabinotiers Grand Complication watch indicates Tourbillon regulator, Sky chart and Sideral hour display. To ensure the moon phases take priority on the front of the watch, the opening revealing the tourbillon regulator has been placed on the back dial. The one-minute-rotating tourbillon is distinguished by its carriage shaped like Vacheron Constantin’s Maltese cross emblem, with its delicately hand-polished bar.

To reduce the weight to improve performance as well as for aesthetic reasons, the tourbillon components have been skeletonised – notably the fixed wheel which is entirely openworked.

The reverse side also displays sidereal time and constellations against a celestial backdrop. This timepiece integrates the notion of sidereal time – also known as “sidereal hour angle” – enabling astronomers to calculate the meridian of the stars.

Using a fixed star in the sky as a reference point, the time it takes the Earth to complete a full 360° revolution – or sidereal day – is exactly 23 hours, 56 minutes and 4 seconds. As the Earth both spins on its axis and revolves around the sun, it takes about four minutes to return to its starting point in relation to the given star.

A fixed dial, bearing a blue dot representing the celestial horizon, is positioned below a movable sapphire crystal engraved with the constellations, while the rim features month markings as well as five-day graduations.

By performing a complete rotation according to sidereal time, this mobile disc gives the exact position of the constellations – delimited by the celestial horizon – at the time when the watch is consulted by pointing it northwards. Sideral time is read off counter- clockwise, facing the current date on the fixed PVD-treated blue outer ring bearing a 24-hour scale along with the cardinal points.

Minute Repeater

To create this particularly complex striking mechanism controlled by a repeater slide housed on the caseband, Vacheron Constantin drew inspiration from the iconic La Tour de l’Île watch.

This double-sided anniversary timepiece produced in a 7-piece edition for the Maison’s 250th anniversary is the most complicated wristwatch ever made with its 16 complications, including a minute repeater with a centripetal strike regulator.

This silent system also found in the Dual moon Grand Complication enables the duration of the musical sequences to be perfectly timed in order to obtain a distinct and harmonious sound of the notes played for the hours, quarters and minutes by the hammers striking two circular gongs.

As an additional feature, the gongs of this repeater have been slightly ovalised to avoid them overlapping the tourbillon and without affecting their crystal-clear sound.

Calibre 2755 TMRCCQP

The Cal. 2755 TMRCCQP is an evolution of the iconic Vacheron Constantin Calibre 2755. This movement has undergone major transformations over the years, notably in the realm of astronomical functions.

The new manual-winding 2755 TMRCCQP calibre is a masterpiece of complexity with its 774 components. Endowed with a 58-hour power reserve, this grand complication beats at a rate of 18,000 vibrations per hour.

Circular satin-brushed and hand-bevelled, with a Côtes de Genève motif on the rear bridges as well as mirror-polished hammers and strike-regulator bar, this in-house movement has been meticulously finished. To ensure a smoother match with the 46 mm-diameter case in 18K white gold, it has also been entirely rhodium-plated.

Technical details

Model: Vacheron Constantin Grand Complication Les Cabinotiers Dual Moon Grand Complication, Reference 9770C/000G-007C

Movement
Caliber 2755 TMRCC QP
Developed and manufactured by Vacheron Constantin
Mechanical, manual-winding
33.30 mm diameter, 11.20 mm thick
Approximately 58 hours of power reserve
2.5Hz (18,000 vibrations/hour)
774 components
50 jewels
Hallmark of Geneva certified timepiece

Functions
Hours and minutes
Minute repeater
Perpetual calendar with retrograde date with instantaneous hand return, semi-instantaneous day and month & year instantaneous
Precision Moon phases and age of the Moon for North and South hemispheres
Sideral hour indication (24H)
Celestial chart
Tourbillon

Case
18K white gold
46 mm diameter
17.10 mm thick

Dials (face & back)
Metal, Sand blasted silvered
18K gold hands and applied hour-markers

Strap
Dark blue Mississippiensis alligator leather, hand-stitched, saddle-finish, large square scales
Buckle 18K white gold folding clasp
Half Maltese cross-shaped

Box
Les Cabinotiers box

Unique timepiece
« Les Cabinotiers », « Pièce unique », « AC » hallmark engraved on caseback