The grand-strike clockwatch is the most complex of horological creations. The greatest difficulty in its construction is to achieve full clockwatch capability from the limited energy available in a wristwatch without compromising on the sound and reliability of the chime.

Constructing this movement has been an exercise in minimizing energy use by maximizing mechanical efficiency. The result is a low-tension movement with gentle mechanisms that have been very finely adjusted to ensure over 35,000 unfailing chimes a year.

Operating a chiming watch has always been risky. If you do the slightest thing wrong, such as setting the time while the chimes are ringing or engaged, you are likely to damage the extremely complex – and expensive – mechanisms inside. Thus, the first entry in the specification book for this watch was: “Make it safe to use by an eight-year-old child.” That eight-year-old child set me the toughest assignment of my career!

To meet this demand, I had to construct a movement on new mechanical principles. In this new watch, ten patents underwrite the “invent” of my watchmaking; the “Fecit” took me five years.
François-Paul Journe

A few months ago I read an interesting book called ‘Stradivari’s Genius’ by Toby Faber. Faber tells the story of the master luthier Antonio Stradivari and his violins through the stories of six of his magnificent instruments: five violins and a cello. These magical works of art were crafted by a grand master; the design was arrived at after years of study and experimentation; and the materials he used were very carefully selected to produce the finest sound. I liked the fact that many of Stradivari’s extraordinary masterpieces are now known, not by a serial number, but by name: a name often borrowed from the instrument’s discerning owner which adds to each instruments individuality. However, I digress; it is another work of art we are interested in here; another masterpiece from a genius of his art; another masterpiece, which is the culmination of many years of experience, research, plain-old painstaking and meticulious hard work; another masterpiece striving for a beautiful, pure sound.

François-Paul Journe assembling his Sonnerie Souveraine. Note: all bench photos are
of either the Sonnerie Souveraine or of Journe assembling the Sonnerie Souveraine

For a company not yet ten years old F.P.Journe has provided us with some of the most interesting and innovative watches available: the unique piece Grand Sonnerie, the Souverain Tourbillon with remontoire d’egalité and dead seconds, the now iconic Resonance, the automatic Octa caliber in its many guises, and earlier this year, the elegant and clean Chronomètre Souverain.

Unique grand sonnerie Tourbillon Souverain

Resonance Chronomètre Souveraine

A completely new caliber is a major undertaking for the largest of brands and as Journe himself said of his new Chronomètre Souverain earlier this year, ‘It took me many, many, years to learn the skills to make a good simple watch'. He may have also added that along the way he also picked up the skills to make one of the most complicated watches known to man . . . and to make it better than ever!

This year F.P.Journe will have presented both their least complicated and least expensive watch to date: the Chronomètre Souverain, which is available only in a precious metal (platinum or red gold), as well as their most complicated and most expensive timepiece: the Sonnerie Souveraine . . . available only in steel.

Before starting his own brand in 1999, François-Paul Journe, like many talented independent watchmakers, worked behind the scenes in the Swiss watchmaking world: providing ideas, expertise and complicated movements to the large brands. One of his projects was to design and build five Grand et Petite sonneries for Piaget; in the contract he retained the right to make one movement for himself. This unique piece was to become the first grand sonnerie wristwatch with F.P.Journe on the dial. The experience Journe gained with those watches gave him a first hand appreciation of the diversity of methods that users could employ to damage the fragile and incredibly complicated movement that is at the heart of a grand sonnerie. Journe promised himself that one day he would make a grand sonnerie which was so foolproof that an eight year child could play with it. (I cannot help but wonder if he chose that age from an unfortunate personal experience)

Of course it isn't enough to simply design a watch like this, parts have to be manufactured for it to come come to life. Journe would not commence making the parts for his prototype until he had his own fully operational manufacturing facilities in-house. The gold movement for the Sonnerie Souveraine is the first F.P.Journe movement to be completely manufactured in their very own workshops (for more on that click here). Having total control of the manufacture of the hundreds of parts needed meant that Journe could ensure that the tolerances and quality were exactly to his specifications and that changes could be made quickly. A watch does not work off a plan no matter how good the computer program - not yet anyway - and it is only in building a prototype that the watchmaker can see the changes F.P.Journe's new manufacturing workshop.
that need to be made. Many of the parts in the Sonnerie Souverain
were re-designed with miniscule adjustments up to six times to ensure perfect functionality; imagine the headaches and delays if these were sourced from a third party.

For a start, Journe’s Sonnerie Souveraine is much more than ‘simply’ a grand sonnerie; it is a grand et petite sonnerie plus a minute repeater. A sonnerie is a clockwatch; that means that it sounds the time (hours and quarters) in passing - just like an old grandfather clock: although a grandfather clock is likely to strike only the hours or perhaps half hours. A grand sonnerie (full strike) sounds the hours and the quarters at each quarter (every 15 minutes), i.e. at 4.45 we would hear four dongs (hours) and three ding-dongs (quarters). A petite sonnerie (small strike) sounds only the hour at the hour the quarters at the quarters, i.e. at 4.45 we would hear only the three ding-dongs of the quarter hours.
A repeater sounds the time on demand rather than in passing - giving us dongs, ding-dongs and dings!

Before we look at the sonnerie let us start with the simpler,
however still extremely complicated, minute repeater. To place the minute repeater in some perspective, it is a much more complicated and a much more complex complication than either a tourbillon or a perpetual calendar.

We rightly revere the minute repeater. We wind it up and it discreetly functions as a normal timekeeper; however, activating a slide on the side charges a spring and the striking mechanism sounds the hours, quarters and minutes. The watch then goes back to being a standard timekeeper until we next activate the slide. Even if we activate the strike mechanism twenty times in a row, we do not reduce the power reserve. To construct a very complicated movement like this, that will not only perform reliably, but also produce a loud, crisp, clear tone when cased, is, very nearly, the pinnacle of the watchmaker’s art. Power or energy is not an issue with the repeater as the strike mechanism is fully wound up each time it is activated. This means that the watchmaker can rely on a nice strong energy demanding spring to providie powerful force to the hammers . . . resulting (hopefully) in a nice loud chime.

The sonnerie works in a different fashion; because it sounds the time in passing, the striking mechanism of the sonnerie demands a continuous power supply. The usual method has been for this mechanism to have its own dedicated mainspring; Journe’s Sonnerie Souveraine however, uses just one mainspring to provide energy to both the escapement and the various strike mechanisms.

What sets the grand et petite sonnerie on a higher plane again from the minute repeater, is not simply the added complication of being able to choose between the watch functioning as a normal time keeper (silent strike), as a grand sonnerie, as a petite sonnerie, or as a minute-repeater - as if that would not be enough! - it is in having to very, very, efficiently manage the power to all of these functions.

Unlike the minute repeater where the strike mechanism has virtually (and comparatively) unlimited power available, the sonnerie is all about power management and conservation. A stronger spring to power stronger energy- sapping hammers means less autonomy for the watch movement. If the parts are not made to the tightest tolerances, if the incredibly complicated movement is not assembled perfectly, then precious energy is wasted and lost.

This tray slowly empties as the Sonnerie Souverain comes together.

It takes a truely great watchmaker to make a grand sonnerie, and I do mean GREAT. There are very, very, few companies, let alone individual watchmakers, in the whole history of horology that have designed and constructed a wristwatch with a functional grand et petite sonnerie with minute repeater. Philippe Dufour was the first in 1992, Gerald Genta and Audemars Piguet followed; now François-Paul Journe raises the bar even higher. Very few experienced watchmakers are capable of assembling and adjusting a minuter repeater . . . it is extremely difficult. Assembling and adjusting a grand sonnerie with minute repeater that simply functions is incredibly hard; assembling and adjusting a grand sonnerie in a size that fits comfortably on the wrist, is virtually foolproof, is designed and adjusted to work reliably for years . . . and sounds clear, crisp and loud: it blows the mind just thinking about it!

Now that we have established just how special the Grand et Petite Sonnerie is in general, let us take a look at how François-Paul Journe has made this greatest of complications even better.