An instantaneous perpetual calendar with
a power reserve extended to 70 days
The Traditionnelle Twin Beat Perpetual Calendar was originally launched in 2019 with an innovative concept: when worn, the watch operates at a high frequency, perfectly suiting modern, active lifestyles. Conversely, when not in use, its in-house-developed Calibre 3610 QP can be deliberately slowed to ensure a significantly extended power reserve. Since then, further technical development of the Calibre 3610 QP has increased the power reserve in Standby mode by 5 days, reaching 70 days in total without any loss of timekeeping accuracy.
User-controlled dual-frequency watch
In 2019, the design of a dual-frequency system integrated into the Calibre 3610 QP marked a new milestone in power reserve management. The movement is equipped with two independent gear trains, powered by a series-connected coaxial double barrel. The first gear, featuring a high-frequency regulation (5 Hz – 36,000 vibrations per hour), ensures that the watch operates with precision in Active mode, whilst the second, with a low frequency (1.2 Hz – 8,640 vph), reduces energy consumption in Standby mode.
A highly technical calibre
Comprising 480 components and measuring just 6 mm thick, the hand-wound Calibre 3610 QP has undergone further technical developments since 2019, particularly in relation to its three differentials.
With the same concern for energy efficiency, research also focused on the perpetual calendar indications, which are executed in a jumping display. Generally, this type of display affects the amplitude of the balance wheel, leading to a loss of precision. To address this, watchmakers and engineers perfected a new double-gear spring-winding mechanism. Operating on a principle similar to that of the first version of the Traditionnelle Twin Beat, this patented system is designed to maximise energy efficiency. Indeed, it requires four times less torque than conventional instant-jump mechanisms, making the date change much less energy intensive.
Seamless transition and extended power reserve
To enhance ease of use, Vacheron Constantin’s engineers developed a push-button-operated switching system set in the case-side at 8 o’clock, with a mode indicator displayed by a hand on the dial. This patented system maintains the display of the time and calendar information during the transition between high-frequency Active mode (5 Hz) and low-frequency Standby mode (1.2 Hz), switching instantly from high to low, and vice versa. By stopping one balance wheel to start the other, there is no interruption to the calibre’s energy chain, thus ensuring a constant display of the time and calendar indications.
A perpetual calendar that comes closest to operating in perpetuity
The perpetual calendar is a noble watchmaking complication that fulfils its promise, provided the movement is constantly wound. It is distinguished by a cam mechanism that enables the watch’s calibre to strictly follow the specifics of the Gregorian calendar until 2100 without intervention. The calibre’s power reserve is therefore of paramount importance in the absence of an automated watch-winding device. With the Calibre 3610 QP, the watchmakers and engineers at Vacheron Constantin have addressed this issue from the user’s perspective, with the aim of extending the autonomy of the perpetual calendar movement without compromising its operation and precision when the watch is not being worn.
A contemporary aesthetic with an openworked dial
The Twin Beat remains true to the design codes of the Traditionnelle collection, with the rounded shape of its case, slim bezel and fluted caseback. With a diameter of 42 mm, the platinum case measures just 12.3 mm in thickness.
Design with purpose
A new openworked dial design accentuates its refined character and innovative spirit, adopting an aesthetic that is resolutely contemporary in style. To optimise the readability of the displays, the power reserve and day and month counters have been modified, and laser-etched glass gives them a frosted appearance that contrasts with the colour of the movement and the guilloché upper dial.
The contemporary aesthetic is enhanced by a strap in textured calfskin with a pin buckle in 950 platinum.
