A Closer Look at Patek Philippe's New Grande Sonnerie Ref. 6301P

In November 2020, a new watch was announced that caught the attention of watch enthusiasts: the Patek Philippe Grande Sonnerie 6301P. It is a true grand complication, equipped with a grande sonnerie, a petite sonnerie, and a minute repeater, all of which reign supreme among complicated watches.

A new lineage connected to Grandmaster Chime

　When talking about Patek Philippe's Grand Sonnerie, the first thing that comes to mind is the Grandmaster Chime 5175, which was released in 2014. However, the 5175 was a special, top-of-the-line model, with only seven examples produced, and equipped with a total of 20 complicated mechanisms, including a perpetual calendar in addition to the chiming mechanism.

　The new 6301P is equipped with a new movement that inherits the lineage of the Caliber 300 used in the Grandmaster Chime, but is more specialized in the chime mechanism, making it the company's first wristwatch to embody the Grand Sonnerie in its purest form. Despite being a complex watch, its seemingly simple design is refreshing, and is the secret to its continued appeal to discerning watch enthusiasts.

　Unlike minute repeaters, which chime the hours and quarters automatically on demand, grand sonneries require a sufficient power reserve to chime the necessary number of gong strikes while maintaining consistent acoustic quality. This model solves this problem by allocating two sets of twin mainsprings (four in total) for the time display and one for the chime mechanism. The former achieves a power reserve of approximately 72 hours, while the latter achieves a power reserve of approximately 24 hours. As a result, the gong automatically chimes a total of 1056 times over the course of a full day, every hour and quarter, while still displaying the time for approximately three days, making this a complex watch practical for everyday use. It's also remarkable that all of this is housed in a movement made up of 703 components, just 37mm in diameter and 7.5mm thick.

　Philippe Barat, head of R&D at the company, said, "The challenge was to incorporate a jumping seconds hand while maintaining the thickness of this movement." In fact, the challenge of this Grand Sonnerie goes beyond the chiming mechanism. Despite its extremely complex internal mechanism, it features a jumping small seconds hand at 6 o'clock, which moves in steps every second. Moreover, instead of using a conventional jumper spring, a silicon gear (release star) and release lever are used, instantly releasing the gear train every second, achieving the jumping seconds. Of course, the use of silicon parts reduces weight and torque loss due to friction, while also enabling the adjustment and control of the gear train's energy consumption. It also reduces the second hand's wobble, and its precise jumps every second not only give the Grand Sonnerie a new, unusual look, but also emphasize its precision.

　The way the movement is displayed has also been given a lot of thought. One of the highlights of the chiming mechanism is the movement of the centrifugal governor, which adjusts the speed at which the hammer strikes the gong. In previous Patek Philippe minute repeaters, this governor was hidden by a Calatrava cross bridge. Mr. Balla says, "To differentiate it from previous minute repeaters, we decided not to cover the centrifugal governor of the new Grand Sonnerie with a Calatrava cross bridge. As a result, you can now fully appreciate the movement of the governor when striking the gong."

　The 6301P perfectly embodies Patek Philippe's philosophy that even a grand complication must be suitable for everyday use. While a chiming watch, the Grand Sonnerie is a distinctive piece that, thanks to cutting-edge technological advances, is distinctly different from a minute repeater. In terms of both its mechanics and aesthetics, this Grand Complication is worthy of being a highlight of 2020.