Blancpain Unveils the Grande Double Sonnerie 15GSQ, a Chiming Watch With Two Selectable Melodies

Grande sonnerie watches are often regarded as the pinnacle of haute horlogerie and watchmaking complications – only a handful of brands, around ten or so, have ever produced them. By a twist of timing, after Chopard last week, it is now Blancpain’s turn to present a grande sonnerie watch. The Grande Double Sonnerie 15GSQ is the most complicated watch ever produced by the brand – surpassing the complexity of the 1735 created with Dominique Loiseau, which combined a tourbillon, a perpetual calendar with moon phases indication, a minute repeater and a split-seconds chronograph. Brilliantly conceived, it features a grande and petite sonnerie, a minute repeater, a flying tourbillon and a retrograde perpetual calendar. You might wonder what hides behind the name Double Grande Sonnerie? Not only does the watch sound a four-tone melody, but you can switch between a traditional Westminster chime and an original Blancpain melody composed by musician Eric Singer.

Creating a grande sonnerie is a gargantuan undertaking, and the Blancpain Double Grande Sonnerie is no exception. Particularly given that this is not any grande sonnerie… To give an idea of the endeavour, this eight-year project required 1,200 technical drawings and 21 patents were filed during the development, 13 of which have been integrated into the final construction of the movement. Its movement comprises no fewer than 1,053 components, all entirely designed, produced, assembled and decorated in-house.

As mentioned in the introduction of this article, the Grande Double Sonnerie 15GSQ is the most complicated watch ever introduced by Blancpain. There is much to explore, but naturally, we begin with its extraordinary chiming mechanism. A grande sonnerie watch, the top-of-the-range for chiming watches, is traditionally associated with a petite sonnerie and a minute repeater mechanism. Both the grande and petite sonnerie strike the hours and quarters automatically, though only the Grande Sonnerie repeats the hour at every quarter. Usually, a pusher or slide allows you to silence the mechanism. The repeater mechanism chimes the time on demand.

World premiere – the double grande sonnerie

Among the specificities of the Double Grande Sonnerie, this fascinating wristwatch chimes times on four notes, and it repeats the four quarters at the hour. Most importantly, there is the possibility to switch between two melodies via a pusher on the case at 8 o’clock – a traditional Westminster chime and an original Blancpain melody composed by musician Eric Singer, the drummer and vocalist of hard rock band Kiss. The slide at 9 o’clock allows you to switch between grande sonnerie, petite sonnerie and silence modes. The pusher at 9 o’clock allows you to activate the minute repeater mechanism to chime the time on demand. The different modes can be checked with indicators on the watch’s face, for instance, W for the Westminster Chime and B for the Blancpain Melody.

For connoisseurs, the inevitable question is: how was this accomplished from a technical perspective? The smart solution implemented by Blancpain is, in effect, almost deceptively “simple”. The Grande Double Sonnerie features two quarter racks, one of each melody, stacked one above the other, and a column wheel allows switching between them, engaging or disengaging each as needed.

Acoustic Performance

The hallmark of a fine chiming watch is its acoustic performance, and the Grande Double Sonnerie does not disappoint – it is loud, clear, and harmonically rich, each note resonating with precision. A joy to hear, it is one of these watches that perfectly embody the emotional magic of chiming watches – where technical mastery meets something truly enchanting.

A multitude of factors influence the acoustic qualities of a chiming watch, and it would be difficult to list all the points Blancpain has considered, but our visit to the Blancpain laboratory was an eye-opening experience regarding the scope of their research… Still, let’s focus on a few key points.

One of the main challenges with such a 4-gong chiming watch is that it is not just about striking time on two tones (ding-dong) but about blending the notes musically into a melody. The two melodies have 16 notes to complete the full hour cycle. The strikework mechanism needs to be perfectly adjusted. Most importantly, the gongs are precisely shaped, adjusted, and mounted. In this respect, Blancpain has filed a patent to set the notes. The gongs feature a (square) variable-shape cross-section, different for each of the four gongs to play a different note. These are crafted from rose gold, which was determined as the best option after testing different materials.

This variable shape for each gong also allows for particularly precise and efficient tuning operations. For each note, the adjustments required are essentially to work on the length of the gongs to hit the right frequencies – often, watchmakers also create a small notch at the base of the gong to adjust the pitch of the note, which is not necessary here. To validate that each of the notes is precisely sounded, Blancpain uses a laser to measure the frequencies of each gong.

The 15GSQ integrates a silent magnetic regulator, so there is no background noise perceptible during the chimes despite its 2,000rpm cadence. This solution is a first for Blancpain (although magnetic regulators have already been used, for instance by Swatch Group sister companies Breguet or Jaquet Droz chiming watches). This ensures a consistent pace for the strikes. Not to mention that there are no “ghost” strikes. With this elegant solution, the minutes will chime the last quarter right away, while some watches leave a silent time.

The case also incorporates a red gold membrane attached to the crystal under the bezel. It has a degree of freedom to vibrate, and its function is to pick up the vibrations from the movement’s gongs and to act somewhat as a loudspeaker, amplifying the sound from the vibrating rings to the watch crystal and bezel. Despite the integration of this solution, the watch is water-resistant to 10 meters, designed to be worn daily.

Safety mechanisms

In this respect, Mark Hayek, CEO of Blancpain, mentioned to us during the presentation of the watch that this was an essential point in his briefing to the development team. “The goal was to craft a grande sonnerie that its owner could confidently wear every day.” As such, the Double Grande Sonnerie integrates multiple safety systems, in particular to prevent damage during handling. For instance, while pulling the crown to adjust the time, you would notice that the chime “bell” indicator would switch to “off” and a chime becomes impossible. The same takes place when the strike work power reserve is depleted. Time adjustments are not possible during a chime.

During the development phase, Blancpain’s quality control conducted tests of the chime mechanism to simulate five years of use, or about 7,000 chimes. The movement was also subjected to shock tests of up to 1,300g.

Calibre 15GSQ with Flying Tourbillon

The highly complicated Calibre 15GSQ of the Grande Double Sonnerie is a hand-wound movement regulated by the brand’s emblematic flying tourbillon, here updated with a silicon balance spring and a 4Hz frequency. Its power reserve is rated at 96 hours for the movement, and 12 hours for the strikework in grande sonnerie mode (14 hours in petite sonnerie mode). The two barrels can be wound via the crown, each in a different direction. Their respective power reserves can be checked at the back of the watch.

Retrograde Perpetual Calendar

The Blancpain Grande Double Sonnerie also incorporates a perpetual calendar with day, month, leap-year, and retrograde date indications. Its mechanism has been newly developed for the occasion. Noblesse oblige, it is integrated directly into the movement instead of relying on a modular construction.

A Blancpain hallmark solution, the calendar indications can be adjusted via practical, patented under-lug correctors. Yet, their construction had to be reimagined to allow for a more compact construction. The return springs of the correctors have been integrated directly into the movement rather than into the case.

Impressive in every respect

The fascinating movement is housed in a 47mm x 14.5mm case whose design is clearly derived from the Villeret collection. We had the opportunity to discover both a rose gold and a white gold version, whose pictures are featured in this article. But for future productions, each piece can be customised according to the wishes of its owner – the material of the case, finishings and even the melody could be adapted.

As you would expect for such a masterpiece, the movement decoration is top-notch. The main plate and the bridges are crafted in solid gold. All parts are meticulously hand-finished with in particular anglage (with 135 inward angles that can only be achieved by hand), perlage, mirror polishing or straight graining.

The Blancpain Grande Double Sonnerie 15GSQ comes on an alligator leather strap and is fitted with a gold folding buckle. It is delivered in a “resonance” box with wood sourced from the Risoud forest in the Vallée de Joux (where the Blancpain manufacture is based). As such, it integrates a soundboard, amplifying the chime. This remarkable, uber-complex watch comes at a price that puts it out of reach for most at CHF 1,700,000, including taxes. It is not a limited edition, but the production capacity is estimated at 2 watches per year.

For more information, please visit blancpain.com.