The Patrimony Ultra Thin Calibre 1731 is a minute repeating wristwatch launched at SIHH 2013. With the development, particular care was devoted to the acoustics of the Patrimony Contemporaine Ultra-Thin Calibre 1731, since its sound is the very reason for being of a striking watch. Various technical choices were made to ensure a crystal-clear and entirely tuneful tone. The gongs are not only connected to the case middle to as to amplify the sound, but also for the first time stacked rather than placed side by side. The case is made to be as one with the movement, within a clever composition incorporating such subtle parameters as the airflow between the mechanism and the case, designed to achieve optimal propagation of the sound. The quest for perfection does not end there, since the case itself has been built without joints so that the elements can interact literally metal against metal and thus enhance the amplitude of the sound, while the flying governor ensures a steady rate of the hammer blows on the gongs. While each master-watchmaker instils his own music into the minute repeater that he will take several months to assemble and fine-tune, the sound of the movement will be subjected to the keen ear of the virtuoso striking mechanism specialists within the Manufacture, and will undergo certain adjustments in order to achieve perfect harmony between low-pitched and high-pitched notes. And it is at precisely at 4:49 that the tests are performed, since that is the time when the cadence is the most clearly audible due to the almost identical intervals between the hours (4 strikes), quarters (3 strikes) and minutes (4 strikes). The true soul of a repeater watch, the individual chime of each watch is recorded and carefully stored before it leaves the Manufacture, thus constituting a “soundprint” duly registered in the Vacheron Constantin archives. This procedure guarantees not only the lifelong repair of all its timepieces, both historical and contemporary, but also the ability to restore within its workshops the unique sound of each model equipped with a minute repeater.
