Vacheron Constantin fixes the most annoying thing about perpetual calendars
The Traditionelle Twin Beat Perpetual Calendar lets you toggle between Active and Standby modes, saving power and extending the watch’s “battery” life.
The convenience of perpetual calendars comes at a cost, and not just the kind that adds several zeroes to a watch’s price tag.
The complication’s ability to track the day, date and month without the need for adjustment until the next century requires its movement to be running constantly. If the watch runs down, resetting it normally calls for a trip to the service centre, as easily adjustable perpetual calendar watches are still few and far between.
Vacheron Constantin counts among the handful that understand the plight of perpetual calendar owners, but has also recently addressed the problem in a completely different way. Unveiled in January this year, the Traditionnelle Twin Beat Perpetual Calendar comes with a whopping 65-day power reserve and, unlike Hublot’s 50-day MP-05 LaFerrari, doesn’t look like a tank on the wrist.
How, you ask? By tackling one problem at a time.
When wearers are empowered with a choice, they are no longer slaves to the mechanics that so enthralled them in the first place.
To extend a watch’s power reserve, one can either increase the size or number of the main-springs or lower the frequency at which the escapement runs. Vacheron Constantin opted for the latter to keep the watch size sensible.
A lower frequency is, however, highly susceptible to external disturbances that will affect timekeeping accuracy, so the Twin Beat solves this issue by having two different balances (powered by the same mainspring barrel): One that runs at 5Hz for normal wear, and another that runs at 1.2Hz for when the watch is not in use.
While in the latter state, the watch continues to keep accurate time and calendar settings for over two months. Wearers need only hit a pusher at 8 o’clock to switch between the “Active” and “Standby” modes.
Now, to prevent any lag when switching between modes the movement, calibre 3610 QP had to be equipped with four differentials. The first two work on the mainspring, allowing the barrels to unwind at different speeds and enabling manual winding respectively. The other two help translate the remaining power onto the power reserve indicator on the subdial.
As all that wasn't challenging enough, the brand decided that the perpetual calendar should also have jumping indicators – a notoriously power-hungry function. To boost efficiency, the Twin Beat features a new “sprung dual-gear compound” that uses only a quarter of the energy normally required in a conventional perpetual calendar. Given how the numbers continue to jump even in “Standby” mode, this was a crucial measure.
If you still somehow manage to let the watch run out of juice, fret not, for the Twin Beat comes with correctors in the case band for easy resetting. It’s a lot of horology packed into a surprisingly svelte 32mm by 6mm platinum case, and it’s refreshing to see all that innova-tion directed at user convenience (instead of precision) for a change.
When wearers are empowered with a choice, they are no longer slaves to the mechanics that so enthralled them in the first place. We can only hope the rest of the industry follows suit in the future.