The Grande Sonnerie is an extremely rare complication in 'wristwatch format' and, in this new Patek Philippe, it is also combined with a small chime (which does not repeat the hours in quarters), a minute repeater (which chimes on demand) and patented small jumping seconds. The Grande Sonnerie Ref. 6301P houses in its platinum case (44.8 mm in diameter by 12 mm thick) a new movement, with 703 components, under the black 'Grand Feu' enamel dial. It should be emphasised that this is the manufacture's first wristwatch to offer the grand strike, the most fascinating of all watchmaking complications, in its purest form, complemented by a small chime and a minute repeater. To give its own interpretation of the grand strike, Patek Philippe has developed a new hand-wound movement derived from the calibre 300, incorporated in the Grandmaster Chime. This is the GS 36-750 PS IRM calibre, distinguished by its resolutely compact dimensions considering the complexity of the mechanism (37 mm in diameter, 7.5 mm thick). One of the main difficulties traditionally faced by manufacturers of large chimes lies in energy control. In contrast to the minute repeater, where the striking mechanism is usually reset every time the user activates the slide or the strike button, the grand strike must have enough energy at all times to strike the desired number of strokes, while always producing a sound of equal quality. To meet this challenge, Patek Philippe has equipped the calibre GS 36-750 PS IRM with two pairs of barrels mounted in series, one for the movement and the other for the striking mechanism. This configuration ensures a power reserve of 72 hours for the movement and 24 hours for the striking mechanism. The user winds the two pairs of barrels through the crown in the position against the case, turning it clockwise for the movement and anti-clockwise for the striking mechanism. The four springs are equipped with sliding balances to prevent any surges. Finally, for the striking mechanism, Patek Philippe chose three classic gongs: low, medium and high. This technical option requires more energy than systems with two gongs. Moreover, it further complicates the watchmaker's work during the meticulous tuning of each gong to achieve the famous "Patek Philippe sound" sought after by Haute Horlogerie enthusiasts.
