A Concise Guide to Striking Watches

By Su JiaXian

Daniel Roth offers an impressive line of high complications - including four different tourbillon calibres - an achievement few companies can claim. The company also makes (yes, in-house at Le Sentier) a minute repeater and a grande sonnerie. No repertoire of complications would be complete without such watches that chime out the time with small hammers and gongs.

Striking watches are regarded as one of the most challenging complications to create, even with all the help provided by modern technology. Not only does the watchmaker need excellent technical skills to finish and assemble the many hundreds of small parts, he also needs the mystical ability to ‘tune’ the sound produced by the hammers and gongs. Many a myth has sprung up about striking watches, including the oft-repeated tale of dipping red-hot gongs in horse urine to achieve the ideal sound.

The most basic form of the striking watch is the repeater. Several species of repeaters exist; all chime out the time on demand, with varying degrees of accuracy. The most basic are quarter and five-minute repeaters. Quarter repeaters chime the hours with low notes and 15-minute segments past the hour with double high-low notes; in essence they only strike the exact time four times each hour. Five-minute repeaters also indicate the hours and quarters, but also each five-minute segment past each quarter with a high note. The most complex form of repeater is of course the minute repeater, which chimes out the time to the exact minute - low notes for the hours, a high-low note for each quarter past the hour and a high note for each minute past the last quarter.

Daniel Roth Minute Repeater in white gold

Some repeaters are also presented with automatons on the dial that move in sync with the chiming of the watch. Ulysse-Nardin is particularly well known for such watches, and Daniel Roth does not have such a watch in its collection as of now.

Repeaters do not rely on the mainspring of the movement for power; instead they are driven by a small spring that is wound by activation of the repeater via either a slide or a button; depressing the button or slide ‘charges’ the spring. The buzz associated with the activation of a repeater is caused by the governor that regulates the unwinding of the spring. Therefore, repeated use of the strike mechanism will not diminish the power reserve of the watch.

In contrast, a sonnerie, or clock watch, requires two barrels and gear trains, one for time display and the other for the striking of the time. That is because a sonnerie strikes the time en passant, as it passes, unless switched to silent mode - not unlike a mobile phone. One type of clock watch is the petite sonnerie, which chimes the hours at the top of each hour, and the quarters past each hour without repeating the hours again. The hour striker is another form of clock watch; it strikes only the hours as they pass.

The ultimate clock watch is the grande et petite sonnerie. It will chime out the hours and quarters en passant (as they pass); some can even chime the hours, quarters and minutes on demand. Developing and manufacturing a grande sonnerie wristwatch is immensely difficult thus only a handful of them have been made; only four companies (or people) can claim this accomplishment. Philippe Dufour famously created the world’s first grande sonnerie wristwatch in 1992; F. P. Journe unveiled his steel-cased watch some years back (based on work done for a Piaget Grande Sonnerie); and Audemars Piguet, with the expertise of Renaud et Papi, produces several different clock watch models.

The four hammers and gongs of the Gerald Genta Grande Sonnerie movement

(Photo by Harry Tan)

The mother of all wrist-clock watches is the movement developed by the Gérald Genta company in 1994. Consisting of a grande et petite sonnerie with Westminster chime (so named because it chimes the same tune as Big Ben in London) on four hammers and four gongs, and also featuring a tourbillon regulator and automatic winding.

A few of these watches were also made with perpetual calendar and second time zone, creating the world’s most complicated and expensive wristwatch at the time. Although the Gerald Genta Grande Sonnerie with perpetual calendar has since been surpassed in terms of nominal complications, the movement certainly remains one of the most complex ever made.

Still one of the most complicated wristwatches in the world

Most of the Gerald Genta Grande Sonnerie watches made in the 1990s were acquired by a single family; the logo at 9 o'clock on the Grande Sonnerie above is the personal emblem of one of the family members

(Both preceding photos from Antiquorum)

Being the sister company of Gérald Genta, Daniel Roth has use of the magnificent Grande Sonnerie movement. Most recently Daniel Roth has created the stunning Grande Sonnerie Moon Phase, a limited edition of 10 watches in white gold. What does it cost? Well as they say, if you have to ask…

Fortunately, Daniel Roth also manufactures minute repeater wristwatches for those on a budget. Like the Grande Sonnerie, the movement in the Daniel Roth minute repeater was originally designed by the firm of Gérald Genta. When the calibre first appeared in 1981, it was the thinnest automatic minute repeater in the world, and easily distinguished by the pusher at 9 o’clock which replaced the traditional slide activator.

I leave you with two photos from Don Corson, AHCI forum moderator, taken during his recent trip to the manufacture in Le Sentier, which show two completed striking watches ready to be shipped.

- SJX

Many thanks to Dr Thomas Mao for his input.

Daniel Roth Minute Repeater in rose gold

Grande Sonnerie with Moon Phase