The manufacture's chiming watches have, for several decades, been an industry benchmark for the quality of their acoustics, the wide selection of models, and the refined combination with other complications. Patek Philippe 's famous Ora Universale timepieces with cloisonné enamel dials are among the most sought-after specimens at auction sales. In these pages we discover all the secrets of an exceptional Universal Hour Minute Repeater Ref. 5531R-012
In the universe of high-end watches, Patek Philippe continues to stand out for its craftsmanship and innovation, especially in the complicated watch segment. Among its most emblematic creations are the minute repeater and Universal Time, both recognized for their technical and aesthetic excellence. These mechanisms are not only a tribute to watchmaking tradition, but also a bridge to the future, thanks to the manufacture's constant research and development.
Dor decades, Patek Philippe's chime watches have been considered a benchmark in the industry, prized for their superlative acoustic quality, wide range of available models, and elegant integration with other complications. In particular, Ora Universale watches with cloisonné enamel dials represent some of the most desired pieces at international auctions, testifying to their priceless artistic and collector value.
A milestone was reached with the presentation of the Minute Repeater Universal Time Ref. 5531, a masterpiece that fuses two of the most prestigious complications in an unprecedented way. This watch represents a first for the Geneva-based maison: the ability to chime local time, the time corresponding to the time zone selected and displayed on the dial. A feature that distinguishes Ref. 5531 from any other minute repeater watch, which traditionally display the time of the owner's time zone of reference, regardless of its geographical location.
The feat of integrating such diverse mechanisms without compromising on performance and reliability underscores the boldness and ingenuity of Patek Philippe's engineers. Despite the technical challenges, the watchmaker has never hesitated to explore new avenues, as demonstrated by other notable innovations, including the famous Grandmaster Chime.
The Universal Hour Minute Repeater watch Ref. 5531 is not only a striking example of Patek Philippe's ability to push the boundaries of watchmaking further and further; it is also a symbol of the unbreakable link between high-quality craftsmanship, technological innovation and timeless aesthetics. With each tick, Patek Philippe never ceases to amaze the world, solidifying its place in the Olympus of Haute Horlogerie.
A BIT OF HISTORY
Watches with the universal time display (world timer), made starting in the 1930s by the Geneva-based master Louis Cottier, is immediately intertwined with that of Patek Philippe. In fact, the Geneva-based house has featured this complication in its catalog since the early days of its presentation, so much so that it has made it one of its most beloved and sought-after workhorses.
Of course, its watchmakers could hardly be content with the albeit ingenious system of simultaneous display of the time of the 24 time zones, with indication of the reference places decaled on the dial or engraved on the bezel. Consequently, in 1999, they decided to improve its functionality thanks to a patented and exclusive mechanism: when changing time zones, the pressure of a pusher allows the set of displays (city disc, 24-hour disc, central hour hand) to be corrected in one-hour increments without affecting the precision of the movement. All that remained was to combine this Universal Hour with the minute repeater to ensure that the watch fulfilled its dual task optimally. The result is the Patek Philippe caliber R 27 HU with minute repeater, Universal Time, and automatic winding, first presented during the 2018 edition of Baselworld with reference 5531R.
But what is the novelty of this model? Simple: until now, the World Timer minute repeaters only chimed "home" time (which was previously adjusted via the crown) because of the independent operation of the two complications. In order for the watch to ring local time, the universal time display (with the moving city and 24-hour discs) had to be mechanically coupled to the striking mechanism.
Let us recall, briefly, how a classic minute repeater works. The heart of the mechanism is composed of three cams called "snails," which have notches: the hour snail with twelve notches, the quarter-hour snail with four notches, and the minute snail with four blades, each of which has fourteen notches. The snails must be in a unique position at all times.
The minute snail is attached together with the quarter nut; the latter is equipped with a cotter pin that, with each revolution, advances the twelve o'clock star that carries the hour snail by one notch. When the minute repeater is triggered by means of the slider built into the case middle, the mechanism goes to "feel" the notches of the different snails in succession to strike the corresponding number of strokes on the gongs. For example, activating the chime at 5 o'clock and 37 o'clock, the hour sensor detects five notches and strikes five strokes on the grave gong. Then, the quarter sensor detects two notches resulting in two sharp-grave strokes on the two gongs, indicating two quarters (thirty minutes). Finally, the minute sensor detects seven notches on the third blade of the minute snail, which results in seven strokes on the high-pitched timbre. All of this is done on a small scale, with intricately shaped pieces, a few millimeters in area and a few tenths of a millimeter thick, with tiny cotter pins and steel springs so thin as to be barely visible to the naked eye.
In the caliber R 27 HU included in the Universal Hour Minute Repeater Ref. 5531, this mechanism has undergone a major modification, with an innovative architecture and components that are the subject of a patent application. While the minute and quarter hands are always fastened together on the chaussée (minute pinion), the hour hand is no longer driven by the quarter hand but is in continuous rotation, driven by the wheel dedicated to the Universal Time time zones. This novel solution makes it possible to index the hour snail to the correct hour, indicated by the hands, to the second. Because in Patek Philippe minute repeats, the passage of the hour is a matter of a second. Example: up to 5 o'clock, 59 minutes and 49 seconds, the watch chimes 5 o'clock and 59 minutes (5 strokes of the hours, 3 double strokes of the three quarters, 14 strokes of the minutes = 25 total strokes), while one second later, at 5 o'clock and 59 minutes and 50 seconds, the watch chimes 6 o'clock (6 strokes of the hours). This 10-second interval is provided so that when the chime ends, the minute hand corresponds exactly to the hour that is echoed.
In the traditional minute repeater, indexing to the second is easier to govern because the hour snail jumps instantaneously by the action of the quarter snail. In the Universal Hour Minute Repeater Ref. 5531, the hour snail is continuously rotating, which greatly complicates the process.
Thanks to a patented solution, however, Patek Philippe was able to solve this problem with the utmost precision and elegance: when the minute repeater is activated by means of the slider housed in the left side of the case, the mechanisms that allow the hours, quarters, and minutes to ring are briefly brought together to resonate the music of time with the acoustic quality and rhythmic harmony that distinguishes Patek Philippe chiming watches.
Simultaneously, the World Timer mechanism is locked so that it is not possible to adjust the time zone during chiming, when the tiny snails, wheels and levers and the tiny rakes are gripping each other. As in every Universal Hour watch from the Geneva-based company, the local time is adjusted by a push-button at 2 o'clock that does not affect the movement's running accuracy in the slightest.
The diversity of the Universal Hour Minute Repeater Ref. 5531 from other Patek Philippe chiming watches also lies in a second patented modification: the two gongs (high and low) are not attached to the movement plate but to the case middle. This choice complicates the assembly of the watch for the watchmaker, but for Thierry Stern, President of the manufacture, who personally tests the sound of each repeater as it leaves the workshops, the effort is amply justified: "because it makes a difference, a perceptible difference in the sonority of this new and extraordinary Grande Complication."
It takes 462 components, all made with extreme precision, finished in compliance with the Patek Philippe Seal and assembled by safe hands, for the caliber R 27 HU to fulfill its functions reliably and melodiously, while guaranteeing the established running accuracy, that is, a tolerance of -3 to +2 seconds per day.
In addition, the movement also possesses a self-winding system with a 22-carat gold mini-rotor inserted at the level of the bridges-a feature inherited from the base caliber R 27, introduced in 1989 on the occasion of the manufacture's 150th anniversary, which enabled Patek Philippe to bring minute repeater wristwatches back into vogue. Thanks to this architecture, the caliber R 27 HU maintains a particularly flat profile despite its complexity, with a thickness that at most reaches 8.5 mm.
With Ref. 5531, Patek Philippe once again demonstrates all its expertise in case design and architecture. Despite its 11 mm thickness, the 18-karat rose gold case profile looks particularly slim and elegant, thanks to the openworked lugs, the beveled bezel, and the shape of the crystal, three details that visibly reduce the external volume. The hand-guilloché Clou de Paris decoration illuminates the case, emphasizing its elegant profile. The same motif embellishes the minute repeater trigger slide in the left side of the case to protect the harmony of the whole.
The sliding cursor surface creates a contrast with its "vertical satin" finish. The time zone button at two o'clock with a polished finish adds a note of shine. The case has a transparent sapphire crystal caseback from which the sophisticated movement can be observed: the bevelled bridges embellished with Côte de Genève decoration, the 22-carat gold guilloché mini-rotor, and the gilded Calatrava cross crowning the inertial flywheel regulator of the striking mechanism. A sight you won't forget even if, then, you prefer to mount the interchangeable solid case back (included) in rose gold.
Another distinguishing feature of this model is its dial, made of 18-carat gold and nickel silver, with an artistically decorated city disc, 24-hour disc and center. Mind you, as with all creations from the Geneva-based House, the design must meet aesthetic perfection and maximum readability. The silvered opaline lacquered cities disc bears the names of the places decaled in black and features a rarity: the Central European time zone is exceptionally represented by the city of Geneva, to complete the reference to the landscape that graces the dial, whereas usually it is Paris. The 24-hour disc lets pink gold appear in the "day" half (7 a.m. to 6 p.m.), with engraved numerals colored in brown and with the Sun symbol engraved, while the "night" half (7 p.m. to 6 a.m.) takes on a brown color on which the pink gold of the engraved numerals and Moon symbol stand out. In the center of the dial, a small masterpiece stands out: the cloisonné enamel decoration depicts a landscape of terraced Lavaux vineyards, a UNESCO World Heritage Site, in front of which the sail of a traditional Lake Geneva boat stands out. Each of these tiny depictions, with its infinite nuances, takes nearly two weeks of work.
The enameler first outlines the pattern with a thin, flat gold wire, which is fixed by cutting on the gold plate. Next, he fills the honeycombs created with enamel powders, which he fires in a special kiln at nearly 850 °C, paying attention to the color changes caused by the high heat. In doing so, layer by layer, he applies different mixtures of opaque, transparent and opalescent glazes, firing after each application, until he concludes this illuminated work depicting the shores of Lake Geneva on a diameter of 17.1 mm. Ref. 5531 is the first and only Patek Philippe minute repeater embellished with cloisonné enamel decoration. Rotating on this evocative image are faceted 18-karat rose gold hour and minute hands with a well-marked central edge. The finely openworked hour hand exhibits the silhouette of the "Southern Cross" constellation, a shape reserved for Universal Hour watches.
