Chiming watches attract less of the limelight compared to tourbillons, being both rarer and less visible. They are also harder to understand, while only the truly serious collector is likely to have the chance to compare different watches directly and in any depth. And in terms of price, these watches tend to push the extreme boundaries of what is rationally comparable; the number of components involved, the array of edges to be polished and the high levels of skill needed to put them all together mark them out as the definition of haut de gamme watchmaking.
Minute repeaters are also the oldest and most traditional of watch complications, though there is an unexpected relevance to today's iPhone-obsessed generation. The invention of a mechanism that could strike the time on demand is credited to an English cleric named Edward Barlow who, in 1678, conceived the rack and snail system that translates clock time into strikes for hours and quarters, the striking being activated by a pull-cord. More famously, the London watchmaker, Daniel Quare, successfully miniaturised the system to fit a pocket watch in about 1700. This was at a time when pocket watches were still little more than an accessory for the rich 17th-century early-adopter, rarely having more than a single hand. (The Huyghens/ Hooke balance spring having only recently become general, precision of minutes a day was as much as could be expected.)
The Credor Sonnerie Spring Drive was first introduced in 2006, with a sound designed to replicate the lingering chime of Japanese bells.
Quare's watch was, by some margin, the most complex and sophisticated portable technology yet made, and in the best traditions of smart phones and tablet computers, successive generations saw refinements and improvements to the idea, such as the use of circular gongs rather than a bell and mechanisms to select passing or demand striking, while costs came steadily down, though chiming watches have never become exactly accessible (Chronoswiss' quarter-repeater probably comes as close as possible). The point where this comparison breaks down is in the pace of change - technological generations that take a year now, lasted decades at the turn of the 18th century.
Nevertheless, it is always something of a surprise to discover quite how long the base technology for even quite sophisticated movements has existed. The essentials of today's minute repeaters were in place within a century - Breguet's all-ornothing device came in at the end of the 18th century - and it is only in the past few years that real change has been seen. So, what are the (absolute) basics of a minute repeater watch?
Patek Philippe's calibre R 27 PS is one of the thinnest movements with a striking mechanism, measuring in at 5.05mm.
The first element is the setting of the spring to power the whole system, while this happens, a mechanism to 'read' the time from the basic gear train comes into action. This has to be done in discrete steps, there being no mid-point between hours, quarters or minutes, and is done by a set of snail wheels with stepped teeth that that turn with the gear train and determine how far corresponding stepped levers, or 'racks', will 'drop' or engage. A separate spring enforces the all-or-nothing lever, which prevents the system trying to work half-cocked. Once, or rather as, the racks read the numbers of hours, quarters and minutes to be struck, the hammers are cocked and released. There is also a regulator system that prevents the striking train from running too fast, without which, the striking train would run out of control once released and is usually in the form of a centrifugal governor wheel.
Over the years, and particularly in the past decade, there have been numerous enhancements to the idea, from Patek Philippe's system for striking a true Westminster chime, a challenge also taken on by Jaeger-LeCoultre and Gérald Genta (now Bulgari), to improved gongs and Jaeger's novel striking mechanism, but the basic idea remains the same. Even Seiko's much-lauded Credor Sonnerie Spring-Drive keeps its innovations for the periphery of the strike mechanism (a miniaturised air resistance governor).
The latest offering from Christophe Claret - the Soprano - features a musically accurate four-note minute repeater striking Westminster Quarters combined with a 60-second tourbillon and Charles X style bridges.
So what of today's crop? Subjectivity is all when it comes to minute repeaters - these are such individual watches, each one is made and assembled as a whole by one of a still tiny band of watchmakers. Patek's gimmicky sounding claim that all their repeater watches are auditioned by either Thierry or Philippe Stern (President and past-President of the company) is actually quite pertinent - they record each watch for archive purposes, not infrequently fail watches and record the work needed to remedy whatever fault of tone or intensity was perceived. The match between the gongs and the case, which serves as amplifier to the chimes, depends on such slight variations that making the match is one of the few remaining areas of watchmaking where skill and experience unequivocally trump engineering and number-crunching.
Patek Philippe is the largest producer, both in numbers made and in the variety it produces, most being grandes complications of one sort or another, as their recent residency at Lancaster House in St James' set out to show. Alongside a selection of the current 13 minute repeaters in the collection, the company had watchmakers on hand to show how it all worked as well as a rather curious display of photographs of watches in their museum collection (why not the watches themselves we wondered?). Star of the show, however, was the ref. 7000R, a simple minute repeater with one of the most diminutive movements of the type ever made at a mere 5.05mm high, which made its debut in the much sought after ref. 3979 that was created to celebrate Patek's 150th anniversary.
The ornate Giocatore is adorned with a handpainted illustration of a 16th-century card player who comes to life when the watch is activated.
Christophe Claret is also a large producer of minute repeater movements, though mostly for other companies. Over the past two decades, Claret's company has worked with everyone from Bovet to Ulysse Nardin, producing some of the most sophisticated watches out there - if you see a minute repeater that is rated as water-resistant (albeit to a mere 30m), the chances are that it originated from Le Soleil d'Or, Claret's HQ in Le Locle. Recent years have seen the Claret name appear on the front of the dial, notably with the Soprano, which combines a Westminster Chimes repeater and tourbillon with another Claret signature: bridges machined from clear sapphire.
You might be surprised to learn that by being based in Le Locle, Claret is, comparatively, an outlier. The Swiss watchmaking industry, spread as it is along the Arc Jurassien (roughly between Geneva and Basel) has quite distinct sub-regions, the main focus of expertise in these watches being the Vallée de Joux, just above Geneva, home to Audemars Piguet, Blancpain, Jaeger-LeCoultre, Bulgari's finewatchmaking facility and even a subsidiary of Patek Philippe that specialises in minute repeater watches.
One of the world's most complicated watches at the time of its release, Jaeger-LeCoultre's Hybris Mechanica Grande Sonnerie is an example of the brand's Trébuchet striking system in action.
Bulgari's inclusion in that list might raise the odd eyebrow; the Roman luxury brand has its main watchmaking HQ in Neuchâtel, but thanks to the acquisition of the Gérald Genta and Daniel Roth brands in 2005, it also acquired the Le Sentier manufacture set up by the much respected Pierre-Michel Golay, one of the acknowledged masters of the art of making minute repeater watches. Watches such as their Giocatore and this year's Carillon Tourbillon go a long way to showing what a serious force Bulgari has become in the small world of haute horlogerie.
Jaeger-LeCoultre deserves a special mention in that its approach to watchmaking problems has always been to design away the problem at source rather than to find 'work-arounds', and the Trébuchet striking system the brand invented is the perfect example. One of the most demanding stages in the assembly of a chiming watch is in setting the hammers so that they strike properly - set too far from the gongs and the strike is too feeble, set too close and the hammer might rest momentarily against the gong, dampening the sound. Jaeger's system incorporates springs into the hammer arm that both control the strike distance precisely and ensure a complete recoil once the gong is struck.
Renowned for its slim movements, Piaget's Emperador Coussin Ultra-Thin Minute Repeater sets a record for this type of complication, with the timepiece clocking at just 4.8mm for its calibre and 9.44mm thick case.
Launching at this year's SIHH is Piaget's contribution. One of the most desirable of recent minute repeaters, Piaget's is remarkable for its incredible combination of diminutive proportions and impressive sound as well as the fact that this is the brand's first truly in-house minute repeater (they wisely brought in external expertise in the development of the movement though). The new Calibre 1290P weighs in at a mere 4.8mm (giving a cased-up height of 9.4mm) and demanded some very neat thinking to achieve the goals set by the product designers, which included water resistance to 30m, self-winding and high acoustic performance.
Piaget has a great store of expertise in making ultra-thin movements, but even this brand's skills are tested to the limit when the design requires wheels that are barely more than 0.12mm thick. The 4.8mm target was behind the (visually successful) decision to place the gongs and hammers on the dial side of the plate, the rest of the dial being the back of the mainplate. Where the designers were more generous was in the diameter of the movement which is 15½"' (34.9mm), a standard movement being 13"' or less. This generosity was not wasted, however - the movement produces tones that are both exceptionally clear (at 64Db it is approaching conversation levels) and sustained, as well as having some nice enhancements such as the system to ensure the hour hand jumps rather than passes through the last second of the hour.