With the L.U.C Grand Strike Chopard achieves one of the most renowned horological complications the grande sonnerie and associates it with a tourbillon. Demanding the grande sonnerie combines a high flying horological mechanism striking the hours quarters and minutes in passing and on demand or standby mode and musicality. This piece is presented nearly 30 years after the founding of Chopard Manufacture in Fleurier at the time we were in start up mode recalls Karl Friedrich Scheufele co president and the originator of this positioning of Chopard in mechanical watchmaking.
A proprietary technology of Chopard
The gongs of the Grand Strike unmatched in the watchmaking industry are the result of a proprietary technology of the house presented in 2016. Carved from sapphire they are integrated with the crystal placed on the dial. Result a sound of singular clarity and a very particular emotion.
Yannick Nardin: Karl-Friedrich Scheufele, the creation of a Grande Sonnerie represents an achievement. But beyond the technical feat, what emotion do you hope to convey to those who listen to it?
Karl-Friedrich Scheufele: Minute repeaters and grande sonneries are watches that open up another dimension—the acoustic dimension of time. What we would like to achieve is to make this acoustic dimension a true experience.
YN: What emotion does the Grand Strike’s chime evoke in you personally?
KFS: It makes me smile every time; it makes me feel good! And even though it reminds us of the passing of time, I think it’s a beautiful way of hinting at it, of making us think about it. But one can also simply enjoy the sound itself, without any further reason.
YN: After succeeding with this complication, considered a pinnacle of watchmaking, do you still have other projects in mind?
KFS: The Grand Strike is certainly a very high goal that we managed to reach. But there is always something else on the horizon to explore. So no, this is not the end of the road.
Striking watches at Chopard
1996 – Founding of Chopard Manufacture
Chopard opens its Fleurier workshops and produces its first in house movement the L.U.C 96.01 L laying the foundations of a true integrated Manufacture.
2006 – L.U.C Strike One
First striking watch from Chopard it automatically strikes the hours on a single gong marking the beginning of acoustic mastery at the Manufacture.
2016 – L.U.C Full Strike
First minute repeater equipped with gongs and a crystal shaped from a single block of sapphire for a sound of unprecedented purity Awarded the Aiguille d’Or at the GPHG 2017.
2022 – L.U.C Full Strike Tourbillon
First minute repeater from Chopard integrating a regulating tourbillon combining chronometric excellence and acoustic signature in monoblock sapphire.
2022 – L.U.C Full Strike Sapphire
Fully transparent sapphire version offering a complete view of the movement and striking mechanism a true tribute to transparency and light.
2025 – L.U.C Grand Strike
First Grande Sonnerie ever created by Chopard combining grande and petite sonnerie minute repeater and tourbillon in a movement of 686 components the result of thirty years of innovation and watchmaking mastery.
A technical insight on the Grand Strike
YN: Florent Zufferey, you are a BT Movement Constructor at Chopard. This watch stands out thanks to its sapphire gongs technology—exclusive to Chopard. How did you overcome the challenges related to the fragility of this material?
FZ: For many years, Chopard has been working with sapphire components in both the movement and the case. One example is the L.U.C Tourbillon Titanium SL watch released in 2007. This expertise has allowed the various teams to anticipate the difficulties linked to the manufacturing and handling of components made from such a fragile material.
Moreover, numerous digital simulations and many practical mechanical-resistance tests were carried out to best determine the acceptable thresholds for each type of stress—whether during operation or in the event of accidental handling.
YN: Why did you choose a square cross-section for the gongs, and how does this change the auditory perception?
FZ: The shape of the gongs’ cross-section stems from the manufacturing constraints of a monobloc sapphire gong plate, but also from acoustic-radiation constraints.
The sound produced by a square-section gong is a subtle blend of radial and transverse vibration modes. This complex vibratory model results in a very rich chime, both harmonious and nuanced to the ear.
YN: You collaborate with HEPIA, Geneva’s School of Engineering, to analyze the very special sound of the sapphire gongs. What does such a scientific approach bring?
FZ: The scientific approach allows us to characterize the sound of our sapphire gongs using physical and psychoacoustic descriptors. It enables us to analyze in detail the modifications and adjustments we make to the elements involved in creating the sound of our watches. We can therefore compare our ideas with those of acoustics specialists. But in the end, the true “judge of peace” is, and always will be, Mr. Karl-Friedrich Scheufele’s ear. The emotion we aim to convey can never be reduced to a list of indicators.
YN: The Grand Strike is the most certified and tested grande sonnerie among contemporary watches. François de Titta, you are responsible for movement prototypes at Chopard. Could you tell us about the challenge represented by COSC certification, the Geneva Seal, as well as the internal tests of 62,400 activation cycles?
FT: The challenge is to ensure that, regardless of the mode of use, the watch displays and chimes the correct time with flawless aesthetics over the long term.
This challenge is full of contradictions. To easily obtain COSC certification, the watch must have very low amplitude variations. But with a grande sonnerie, these amplitude variations are inevitable. So the regulating must be mastered with great precision to keep the movement stable and accurate despite these fluctuations. Next, each component must be decorated according to the criteria of the Poinçon de Genève, with the utmost care, so as not to alter its dimensions or impair its proper functioning. And finally, the aging tests confirm that the entire design is robust over time, ensuring that the watch can be passed down to future generations while preserving its full reliability.
