In developing this state-of-the-art timepiece, Patek Philippe sought technical inspiration from – believe it or not – antique gramophones
The Patek Philippe Advanced Research Ref. 5750P is the first chiming complication in the manufacture’s Advanced Research line. Knowing how minute repeaters, sonneries and other striking timepieces are practically sacred to the manufacture, this watch delivers what is undoubtedly Patek Phillipe’s most powerful, symphonious, and crystal clear chimes to date. According to the manufacture’s internal tests, the chimes of a standard Patek Philippe repeater such as Ref. 5078G can be heard over a maximum distance of 10 metres. Those of Ref. 5750P, however, can travel up to 60 metres.
Yet it is cased in a material which according to conventional wisdom is the least conducive to the transmission of sound – platinum. “What kind of wizardry is this?”, you ask? Well, that’s nothing but the latest, most innovative sound amplifying system ever to emerge from the Advanced Research labs of Patek Phillipe.
Known as the fortissimo module, it is essentially a mechanical loudspeaker but instead of a flexible diaphragm or membrane for sound amplification, it uses an oscillating wafer made of synthetic sapphire no more than 0.2mm in thickness.
This component, along with a flexibly suspended sound lever, plus a titanium ring with four perforated slots acting as acoustic channels, forms the key technical thrust in Ref. 5750P which has four patents filed. Two for the fortissimo module alone, and two more for the hammers (being made of platinum) and the gongs (being helical in shape with a coplanar attachment assuring evenly amplified high and low chimes). Here’s a quick video of how it works.
The result of three years of hard labour, this state-of-the-art invention shines new light for minute repeaters of the future, even as it draws inspiration from the past. Matter of fact, the Patek Philippe Advanced Research team had gone all the way back to the origins of sound making.
Loud and clear
Antique phonographs invented in the late 19th century provided the theoretical blueprint of Ref. 5750P. Indeed, this is the first time in the field of sound that a phonograph had come to inspire a minute repeater. The key objective thus was to amplify the chimes of a minute repeater by transmitting the vibrations of the hammer to a vibrating plate using a lever mechanism, so that the sound projects not only louder but also remains pleasant.
Once the hammers strike the gongs, the gongs cause the lever to vibrate which in turn causes the sapphire plate to vibrate. An insulation rim made of a high-tech composite material acoustically uncouples the amplifier from the movement. Sound travels from gongs to lever to sapphire plate, radiating outwards, escaping through the titanium ring with four acoustic channels secured between the case and case band. Because these vibrations no longer travel through the case as with standard minute repeaters, choice of case material has no direct influence over efficiency of amplification and sound diffusion.
So thanks to the fortissimo module, even platinum, the densest precious metal which is notorious for muffling sound, may produce the most euphonious of chimes. Rich, colourful, round, and with a long flourish towards the end leading each chime to last just a smidge longer. Happily for Ref. 5750P, Patek Philippe increased by three seconds the time allocated between strikes of the hour, quarter, and minute hammers, so the mechanism stretches to a maximum of 20 seconds for its longest set of chimes, 12 hours and 59 minutes.
Comparing the acoustic signature of Ref. 5750P with another minute repeater based on the same movement, the results are startling. The attack of the hours and minutes are significantly stronger with the fortissimo module. Fortissimo also favours low frequencies over high frequencies.
Using platinum for its repeaters has always been Patek Philippe’s preferred way of showcasing its unrivalled technical prowess with chiming watches, and as all its aficionados know, you could always spot a platinum Patek Philippe by the single round diamond set at six o’clock on the case.
That Patek Philippe took a trip back in time to develop ideas for the future might sound a little paradoxical until you realise that the manufacture has always sought to learn and relearn lessons from the past. Its expertise with contemporary minute repeaters, for instance, comes from years of in-depth research on antique and vintage repeaters. The r&d team, in addition to president of Patek Philippe Thierry Stern, would listen to the chimes of old minute repeaters, gleaning important details from them to bring this ancient complication into the future.
A minute repeater represents the pinnacle of watchmaking know-how and yet it is, ironically, the easiest to criticise. Recognising this, Stern has said: “Even if you don’t know anything about watches, you can judge for yourself if the sound is not the best.” Today, Patek Philippe leads the world in the production of minute repeaters not just by having the largest collection in regular production, but in the way they are assessed.
The chiming of every timepiece is listened to personally by Stern, and recorded for the Patek Philippe archives, before it may leave the manufacture. This way, even though every repeater has its own unique sound, carefully fine-tuned by each individual watchmaker, collectively they all have what is informally known among collector circles as the Patek Philippe sound.
Ref. 5750P operates on a modified version of the classical Calibre R 27 PS minute repeater with small seconds, where the gongs are disconnected from the movement and case, but connected to the fortissimo amplification system. The patented platinum hammers, however, remain connected to the base movement in order to receive the impulses from the gathering pallets when the striking mechanism is activated. Soft yet denser than steel, they elicit gentle and lighter notes than steel hammers with no compromise on sonority, but were a nightmare to finish—it took a single watchmaker four hours to bevel and polish just one of these hammers.
Likewise, manufacturing of the platinum case was no cakewalk. The entire structure including its four lugs were machined from a single piece of raw platinum because Patek Philippe was not satisfied with the appearance of welded lugs on a platinum case. Finishing of the lugs alone, excluding the case, took six hours to accomplish.
Platinum was also used for the micro-rotor and in spite of the thinner design delivers the same winding efficiency as the 22K gold one found in standard Calibre R 27 PS. Its reduced dimensions allowed the sound bridge to slip under the sapphire plate without adding anymore millimetres to the overall height of the case. The result is a sleek, elegant timepiece no more than 11.1mm in height and a very modest, timeless 40mm diameter.
Finally, even though the fortissimo ff module endows Ref. 5750P with the boldest chimes ever to grace a Patek Philippe repeater, the watch’s design is anything but loud. Its five-part dial was elaborately constructed to evoke the spoked wheels of vintage automobiles. Time is indicated by Dauphine hands in white gold and applied kite-type hour markers in blackened white gold. Over the micro-rotor, the same ray pattern appears but this time created by a laser-based light-absorbing surface texturing technique rendering certain segments to appear black.
The only physical element that might be described as loud would be the shiny bright orange alligator strap with its black contrast stitches. But then again, when you’re one out of just 15 people in the world wearing such a magnificent timepiece, you’d definitely want people to be able to see and hear it from 60 metres away.