Insider: Vacheron Constantin Traditionnelle Twin Beat Perpetual Calendar. A Feat of Horology that Blends Classic and Modern Watch Design Cues.

A big highlight of the SIHH 2019 and a true feat of horology is the new Vacheron Constantin Traditionnelle Twin Beat Perpetual Calendar. Inspired by the seasonal system from the Japanese Edo Period which divided day and night into six segments —of which the length varied from day to night and from one season to another—, the clocks from this period were equipped with a single or double foliot balance enabling automatic changes in their operating speed. And just like those clocks, the Traditionnelle Twin Beat Perpetual Calendar beats at a high frequency when worn and on demand, it can be slowed down by pressing a pusher in order to guarantee an extended outstanding power reserve of at least 65 days when the watch is not been worn. An incredible power reserve never achieved before by any other wristwatch.

Things to Know About the Watch

The Vacheron Constantin Traditionnelle Twin Beat Perpetual Calendar is equipped with a 42 mm case in platinum and a partially openworked look that is accomplished by the use of a sapphire disc on the lower half of the dial. Displaying the hours, minutes, date, month, leap year and power reserve on its dial, the watch is still quite slim —12.3 mm thick— despite the highly complicated movement with its extended power reserve.

The Traditionnelle Twin Beat Perpetual Calendar utilizes a patent-pending mechanical system that allows instantaneous switching between Active mode where one balance wheel beats at a frequency of 36,000 vph —5Hz— or Standby mode where a second balance wheel beats at less than a quarter of the frequency during active mode at only 8,640 vph —1.2Hz.

By pressing a pusher located on the left caseband at 8 o’clock, the wearer can switch the operation of the watch between active and standby mode. A clever indicator on the dial displays 5Hz and 1.2Hz for whichever mode is selected. A very useful complication for when a perpetual calendar is not been worn, relieving the owner from the meticulous and tedious process that it represents to set the calendar every time that the watch has ran out of power reserve and not been worn for days, weeks or months.

On its split grey and sapphire dial, the very 18th-century art of engine turning and frosted finish are transmuted into clean radial guillochage and sand-blasted surfaces. In order to perfectly achieve this union of tradition and modernity, the dial is made in two main segments in a multi-stage process. A gold dial segment is decorated with hand-guillochage, and then fitted within an outer segment of sapphire crystal. Gold hour indexes are then set into the sapphire crystal dial segment, which is further laser-engraved and ink-filled for a sleek, seamless appearance.

A color coded power reserve indicator at 12 o’clock indicates the power reserve for either frequency mode. While the Vacheron Constantin Twin Beat can provide a power reserve of only 4 days while beating at 5Hz, it can deliver an impressive 65-day power reserve while beating at 1.2Hz on standby mode. Both the Active and Standby balances are driven by the same mainspring barrel, which is the most efficient way of distributing energy and the only way to have a single power reserve indication. 

Lastly, in order to maintain the guilloché design intact, the Vacheron Constantin logo is printed in white on the sapphire crystal rather than on the dial itself.

Perpetual Calendar Indications

The perpetual calendar indications are positioned at the bottom of the dial and fitted with sapphire crystal discs that have been ink-filled for optimal readability. While the day of the week is not indicated by the Vacheron Constantin Traditionnelle Twin Beat Perpetual Calendar, the watch does indicate the month at 5 o’clock, the date at 7 o’clock and the leap year at 6 o’clock. The use of a sapphire crystal on the lower half of the dial allows for incredible views of the manual wound calibre 3610 QP underneath.

In the traditional Vacheron Constantin way, the different components of the movement including gears, wheels and levers are exquisitely decorated with satin-brushed finishing, circular graining, snailing and côtes de Genève rayonnantes. A visual symphony and a real treat for the eyes. The watch is delivered on a beautiful gray alligator strap matching the color of the upper half of the dial.

The Movement

Exclusively developed for the new Vacheron Constantin Traditionnelle Twin Beat Perpetual Calendar comes the new manual wound in-house calibre 3610 QP. This movement composed of 480 parts is only 6mm thick and 32mm in diameter. An impressive feat of horology and micro-engineering on its own, this movement is fitted with two balance wheels and only one of them is allowed to oscillate at a time. Due to this, the hour and minute hands have to draw variable information from two gear trains for one reading of the time. This is accomplished by a gear differential that allows the hands to read more than one input source of timekeeping data. A second differential is mounted on the barrel for the dual purpose of winding the mainspring and also reducing the mainspring torque as it is directed towards the Standby mode balance equipped with a very delicate hairspring that was especially created for the slow-beat balance. Two final differentials translate the power reserve into the subdial that indicates the remaining mainspring wind.

The smaller balance wheel beats at a frequency of 36,000 vph, while the bigger balance wheel beats at a frequency of 8,640 vph. The movement plates and bridges are decorated with Côtes de Genève and then treated with NAC, a dark coating that offers superior resistance and durability compared with other similar-looking treatments, in addition to giving the watch a more modern and contemporary look when turning the watch over.

On the Wrist & Pricing

On the wrist, the new Vacheron Constantin Traditionnelle Twin Beat Perpetual Calendar wears true to its actual size and simply impeccably. A true feat of horology that blends classic and modern watch design in one of the most advanced and functional complications. For the money, this is a lot of watch that you just can get elsewhere. Kudos to Vacheron Constantin for proving once again their prowess as the oldest watch manufacture in the world.

Sticker Price $199,000 USD. For more info on Vacheron Constantin click here.