An alliance of tradition and engineering for the ultimate Grande Sonnerie, the most complicated of its kind in the world for over 15 years.

The latest evolution of the Arena Grande Sonnerie, the Arena Metasonic raises the exclusive work of Gérald Genta to the realm of perfection. Launched as a wristwatch in 1994 and regularly improved ever since, the noble proprietary complication that was already considered beyond compare further enhances its pedigree by appearing in a revolutionary new case. An original material and unprecedented construction combine to ensure an enchanting chime, embodying progress stemming from in-depth acoustic and vibratory research that simultaneously overturns certain preconceived ideas.

Striking watches

Striking watches are classified into quarter, five-minute and most frequently minute repeater models, and Grande Sonnerie or “grand strike” variations can be triggered up to 35,040 times a year. They strike the hours and quarters automatically or “in passing”, as well as being systematically equipped with the minute repeater which strikes the hours, quarters and minutes on request. The watch then successively chimes the hours on a low-pitched gong, the quarters on two, three or four gongs, and the minutes on a high-pitched gong. Grande Sonnerie watches are a long-established speciality at Gérald Genta. It has introduced a number of exceptionally complex wristwatch models since 1994. With their four hammers and their Westminster chime playing a different tune for each quarter, they represent 15 years of peerless accomplishments and are all the more remarkable in that they are developed on tourbillon movements. The Grande Sonnerie models comprise approximately 850 parts for the hand-wound models, 950 for the self-winding versions, and 1,100 for those equipped with a perpetual calendar. It takes around a year’s work to craft just one such watch, and only 61 in all have emerged from the Gérald Genta workshops since 1994. Connoisseurs, and especially master-watchmakers, unanimously confirm that it is not the accumulation of functions that makes a watch complicated, but instead the intrinsic complexity of the movement to be assembled and cased up.

Traditional movements

While Gérald Genta is a brand famed for its daring approach to watch exteriors, it is nonetheless extremely respectful of traditional horology, as is confirmed by the superlative workmanship displayed in its authentic Haute Horlogerie movements featuring a wealth of hand-crafted decoration and finishing. Among them are striking watches, which can be viewed as the last bastion of pure watchmaking artistry. Whereas virtually any other movements can now be industrially made and thus identically reproduced according to predefined criteria, a striking mechanism necessarily calls for manual intervention. The watchmaker adjusts the length of the gongs or their point of attachment in order to achieve the desired notes. This delicate exercise is generally performed by ear, with the inherent risk of never achieving the same result twice, even when the same person is involved. Gérald Genta therefore decided to solve this particular problem and its striking watches have now been effectively standardised to measurable norms for the past four years.

Standardised striking watches

Based on research conducted in cooperation with an acoustic laboratory, Gérald Genta has an exclusive software programme enabling it to measure the sounds produced in particular by its Grande Sonnerie watches. Three main criteria have been established. First of all, the intensity or the force of the notes: to earn approval, they must demonstrate a level of intensity sufficient to ensure they are clearly audible, but not excessively high in order to preserve their harmonic quality. The harmony or the correct pitch of the notes is then checked to ensure a sol (G) is consistently sounded for the hours, do, re, mi and sol (C,D,E and G) for the various combinations of quarters – more specifically mi-re-do-sol (E-D-CG), re-sol-mi-do (D-G-E-C) + mi-re-do-sol (E-D-C-G), mi-do-re-sol (E-C-D-G) + re-sol-mi-do (D-G-E-C) + mi-re-do-sol (E-D-C-G) – and re (D) for the minutes. All are the notes are within the fifth and sixth octaves, ensuring they are low enough to be truly melodious. Finally, the cadence or regularity in milliseconds is verified according to defined intervals between each hour (628 ms), each quarter (427 ms) and each minute (509 ms). The goal is to ensure an harmonious sequence with clearly perceptible sounds. Thanks to these measurements, each completely independent of the others, Gérald Genta Grande Sonnerie models are now all of reliable equal quality. Fine-tuning by the watchmakers is still indispensable, but now converges towards common criteria guaranteeing a unique tune. It takes an average of 12 successive controls to achieve the desired result.

Source: Worldtempus