Unlike other minute repeaters, where the shape and material of the watch case determine the quality of the sound, Audemars Piguet’s groundbreaking Royal Oak Concept Supersonnerie works independently. Global brand ambassador Claudio Cavaliere explains its mechanics.

At the SIHH two years ago, Audemars Piguet CEO François-Henry Bennahmias stunned a roomful of journalists into silence when he activated the striking mechanism on the Royal Oak Concept RD#1, then just a prototype. The silence did not last very long, as murmurs quickly reverberated around the room. The audience was clearly impressed by the volume, tone, clarity and pitch of the chime, though the burning question on everyone’s mind was how the melody was achieved.

The answer was finally revealed a year later with the Royal Oak Concept Supersonnerie, the production model of the prototype, and one of the loudest minute repeaters on the market, thanks to a complete rethinking and reworking of the repeating mechanism. We are told that 20 pieces were produced in 2016 and another 20 will be made this year. One of those pieces made its way to Singapore last September, accompanied by Audemars Piguet’s global brand ambassador Claudio Cavaliere.

“This watch has some improvements from (the prototype): We reduced the gap between the hours and minutes when there are no quarters. We also invented a security system which makes it impossible to set the time when the watch is striking. The third difference is that (in 2015) it was a prototype, but (from 2016 onwards) it’s for sale,” says Cavaliere.

The first improvement begs explanation. Say the time is 10 minutes past four. In a typical minute repeater, the mechanism would strike four notes for the hour, followed by a silent pause, and then 10 notes for the minutes. In the Supersonnerie, the length of that pause is reduced so the user does not have to wait to hear the full chime. It is Swiss efficiency at its best.

“Historically, the sequence was made in a way that we targeted to have a pause after every strike. Once [there were] no quarters, [there was] a pause and then a strike. With the new features, the sequence is different: The cumulation of the silence is at the end of the sequence,” Cavaliere explains, adding that no additional mechani cal components were required to bring about this change.

The Supersonnerie is housed in a 44mm titanium case and boasts an open-worked dial. It was 10 years in the making. The idea for it sprung from a casual remark by a guitar-maker friend of an Audemars Piguet watchmaker. “I like your watches,” the friend declared. “But as a musical instrument maker, I feel your minute repeaters [sound] as if someone was sitting on the guitar.” Music, he added, is all about vibration.

The watchmaker reflected on this simple yet profound observation. In a typical minute repeater mechanism, the gongs are arranged on the mainplate, along with other components. It is a crowded configuration and to expect a clear chime is like trying to get a message across to a friend in a packed, noisy room.

“So we tried to separate the watch’s acoustic functions from the other functions,” says Cavaliere. “In the new structure, we have a case back with holes and a new device called a soundboard. The gongs are attached to this device, so the vibrations [move] from the gongs to the soundboard, through the air and out through the holes. This is a way to amplify the sound. But we don’t want to amplify just any sound; only the pure, beautiful sound of the gongs.”

The soundboard is made of a copper alloy, one of the best materials for the job. The holes in the case back are like those on a guitar, allowing vibrations to emanate, reflect on the wearer’s wrist and disperse into the air, eventually reaching the eardrums as a robust, distinct melody. Despite these significant improvements, there was still work to be done to refine the sound quality.

Cavaliere explains: “We managed to amplify the sound, but we also amplified the unwanted noise, such as [that] of the striking regulator — which controls the rhythm of the minute repeater. It’s a rigid anchor that moves in two directions to make the timing regular. It’s very stable and has been in existence since the 19th century, but it’s very noisy.” The noise in question is the mechanical whirr in the background when one activates a striking watch.

To counter this, the watchmakers proposed using a shock absorber. But instead of incorporating an additional device, they simply modified the existing anchor design, making it flexible rather than rigid. At each point of impact, this flexibility allows the anchor to absorb the shock and, ultimately, the noise. “The anchor is made of steel and it is 0.15mm thick, much like a strand of hair,” Cavaliere explains. “And it’s all polished and decorated by hand. In its lifetime, that little element can absorb 1.5 million shocks. We tested it for 15 years of wear and it didn’t break.”

In other words, if you purchase and receive your Supersonnerie this year, you will not need to replace the anchor until at least 2032.

Does the brand have a buyer in Singapore? “Potentially, yes. This is why we’re here! Of course, the range of people interested in this watch is limited [compared with] the rest of our production. We’re targeting our points-of-sales and boutiques that have connections with such clients,” he says.

All these technical achievements helped the Supersonnerie scoop the Mechanical Exception award at the 2016 Grand Prix d’Horlogerie de Genève in November. The question, of course, is what these advances mean for the brand’s regular minute repeater production. “We’re targeting to use this case design in future repeaters. On round cases, on grand complications. But we won’t use it on all minute repeaters, for reasons of exclusivity. You don’t want to have too many of these watches in the market.”

Besides chronicling developments in the luxury watch industry, Aaron De Silva also runs The Time Traveller SG on Instagram (@thetimetravellersg) and Facebook (www. facebook.com/thetimetravellersg)

This article appeared in the Options of Issue 761 (Jan 9) of The Edge Singapore.