Blancpain unveils the Grande Double Sonnerie 15GSQ, its most complicated timepiece with flying tourbillon, perpetual calendar and a Grand Sonnerie.
Blancpain has unveiled the Grande Double Sonnerie, a timepiece that stands as the most complicated in its history, integrating a flying tourbillon, a retrograde perpetual calendar, and a groundbreaking chiming complication that offers two selectable melodies.
Conceived by President and Chief Executive Officer Marc A. Hayek eight years ago, the project aimed beyond the creation of a conventional grande sonnerie and sought to advance the art of horology by introducing something genuinely unprecedented.
The development resulted in 21 patents, 13 of which are incorporated into the final movement, and the manual winding Calibre 15GSQ composed of 1,053 components out of a total of 1,116, all designed, produced and finished entirely in house.
The core innovation of the watch is a world premiere, the ability to sound the time using two distinct and selectable melodies, chosen via a pusher on the case.
The first is the classic four note "Westminster" chime dating back to 1793, and the second is an original composition, labeled "Blancpain", created for the project by musician and collector Eric Singer, best known as the drummer of KISS.
A smooth feel to the selection button as it switches between the two is ensured by the mechanism’s column wheel.
This construction requires four separate hammers playing the notes E, G, F and B, a level of complexity that demands scientific precision in both pitch and tempo.
Blancpain’s watchmakers use lasers to test and adjust the gongs, while the tempo is governed by a patented silent magnetic regulator and further refined by microscopic adjustments to the striking mechanism.
The gold sounding rings were selected after extensive research to deliver the most refined acoustic result.
Unlike other grande sonneries, the Blancpain model offers an extended performance on the hour, sounding both the hours and the full sequence of the four quarters. Sound transmission is enhanced by a gold acoustic membrane integrated into the bezel. You can listen to the chiming in this reel from our Instagram account.
The manual winding Calibre 15GSQ, which measures 35.80 mm by 8.50 mm, unites the dual melody sonnerie with a flying tourbillon and a retrograde perpetual calendar.
The winding system is unique, allowing the power reserve to be wound manually in both directions. The movement features two independent barrels, one providing 96 hours of power for the going train and the second delivering a significant 12-hour reserve dedicated to the chiming mechanism in Grande Sonnerie mode.
The flying tourbillon operates at a frequency of 4 Hz (28,800 vibrations per hour) and is equipped with a silicon balance spring for enhanced chronometric performance.
In a departure from convention, the retrograde perpetual calendar is fully integrated into the movement to preserve an unobstructed view of the sonnerie mechanism.
The patented under lug correctors have been redesigned and incorporated directly into the movement structure to accommodate the acoustic membrane.
The timepiece is a remarkable exercise in haute horlogerie finishing.
The mainplate and 26 bridges are crafted from 18-carat gold, a material selected for its warm appearance yet demanding exceptional skill due to its delicacy.
The movement showcases elaborate hand finishing, including mirror polishing, diamond milling and straight graining.
Particularly noteworthy are the 135 sharp internal angles, each created and refined by hand using successive abrasives and stems of gentian wood.
This meticulous attention ensures that finishing is applied not only to visible surfaces but also to hidden ones. The assembly of each movement, representing nearly twelve months of work, is entrusted to one of two dedicated master watchmakers, Romain or Yoann, who each engrave their signature on the movement.
Despite its technical complexity, the Blancpain Grande Double Sonnerie is designed to be worn. The watch measures 47 mm in diameter with a thickness of 14.5 mm and is offered in two variations, in red gold (ref. 15GSQ-1513-55B) or white gold (ref. 15GSQ-3613-55B).
It is presented in a special case crafted from wood sourced from the Risoud forest, which acts as a natural soundboard to amplify the chime and link the timepiece to the acoustic heritage of the Vallée de Joux.
Production will be strictly limited to two timepieces per year, ensuring absolute exclusivity and allowing for personalisation. blancpain.com
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