When Audemars Piguet first showed the Royal Oak Concept Supersonnerie in SIHH this year, the halls were abuzz with collectors and journalists asking each other if they have already heard the sound of the minute repeater. Most reports then was that the sound is very loud, very clear, but perhaps needed a bit more tuning to sound beautiful. Fast forward to October, and in a special event to launch the watch in Singapore, we got a close look and listen to the marvel, and came away awed. There are three new concepts put forward by AP to achieve the superb sonics, and we will explore each in turn in this review.
The watch was first presented as a concept in 2015 as the Audemars Piguet Royal Oak Concept RD#1. We covered the essential information of that release in the link. The production model following the concept exploration of the RD#1 is now incarnated in this new, commercially available Royal Oak Concept Supersonnerie. The watch is cased in a titanium case, with a titanium bezel, and a ceramic crowns and push pieces for the chronograph, and is water resistant to 20m.
The dial is black openworked with black counters, white gold hands with luminiscent coating and a black inner bezel, and looks almost the same as the RD#1.
The Singapore launch was held at Infinity Studios, a sound post production facility. The room where the presentation was held boasted of state of the art acoustics, and equipment to match.
Recording the repeater
Before we cover the innovations, let’s take a look at the common problems faced by traditional minute repeaters. First the room full of state of the art sonic equipment was put to good use. An Audemars Piguet pocket watch minute repeater from the turn of the century (1900s) was made to strike. The sound of the strikes were loud and clear. And even in the very quiet, acoustically treated room, the buzz of the regulator was not detected from where we were seated, a distance of about 3m from the watch. But holding the watch close on one’s hand, the buzz of the regulator can be clearly heard, albeit softly in the background. A graphical representation mapping each tone over time shows the following curves:
Then an Audemars Piguet wrist watch with a minute repeater from the 1920 was sounded. This is a small watch, using an extra-thin caliber 9½SMV6. The sound can barely be heard from where we were sitting about 3m away. On closer examination from about arm’s length, the strikes are very clear, but very soft. The chart is shown below:
And finally the Royal Oak Concept Supersonnerie. It was loud, clear and easily heard from 3m away. At arm’s length, the strikes had a high intensity accompanied with a good tempo. The regulator was largely silent until one holds the watch to one’s ear while it is striking. The graph shows the following:
So subjectively, as compared to its forbears, the pocket watch and 1920s small wrist watch, the Supersonnerie’s strikes are as loud or louder than the pocket watch, have a harmonic richness which is equal to both and a noise floor which is comparable to the small wrist watch of the 1920s. Seemingly a “Best of both worlds” scenario. So how did AP achieve this?
AP established a Sound Lab program in collaboration with the Ecole Polytechnique Fédérale de Lausanne (EPFL) in 2006. This lab is a dedicated community of watchmakers, technicians, academics and musicians who explore the sound of the minute repeater and try and push the envelop towards a more perfect performance. This lab developed the following three innovations which are incorporated in the RD#1 and the Supersonnerie.
The Sound Board
The classical minute repeater consists of a set of steel gongs fixed to a mainplate so that the chiming sound is transmitted via the watch’s movement, through the mainplate and other components and communicated to the case. In the Supersonnerie, AP considered a system much like that of an acoustic guitar or stringed instrument.
As the string is plucked or strummed, the sound from the string is enriched harmonically by the enclosure of the guitar box, and is amplified and transmitted through the sound hole towards the listener. The AP Sound Lab hit on this concept and used it as a model for their repeater.
The construction of the Supersonnerie is very similar to that of the guitar. The gongs behave like guitar strings, the hammers being the analog to the guitar players fingers plucking on the strings. The gong stud were the gong is soldered to acts like the guitar’s bridge, and the internal soundboard spread beneath the movement is the body of the guitar. The soundboard in the Supersonnerie acts much like the sondboard of the guitar, the volume encapsulated enriches the harmonics, and amplifies the strikes, and propels it out through the vented case back seen at the bottom of the blowup diagram above.
The soundboard made of a thin plate of titanium, but it is conceivable that it can be made of stiff paper or wood. Titanium was selected because it is more stable, and can be subject to ingress of water as the watch remains water resistant, but water can enter into the soundboard chamber without entering the movement proper.
The Silent Regulator
Next, AP tackled the problem of the buzzing regulator. Lovers of traditional minute repeaters often love the buzz of the regulator. The regulator times the tempo of each strike. Too fast, and the repeater sounds like its in a hurry. A stressful situation. Too slow, and it seems lazy and languid. But strike at the right tempo, like music, it stirs the excitement, and creates a certain elation. So a well tuned regulator is essential. Some love the sound of the buzzing regulator, but others loathe it.
But AP’s Sound Lab figured that a silent regulator, making a dark noise floor is better to appreciate the strikes. So they went about to redesign the strike regulator. The spinning regulator is re-designed to have a more flexible anchor system so that it absorbs the hum. This is not the first time minute repeater engineers have tackled this problem. This is quite ingenious, as the flexible anchor now flexes instead of strikes the cogs as it goes about its job of regulating the speed of the wheels.
The watchmakers at Seiko Credor Spring Drive Minute Repeater use air resistance to silence the regulator. They needed this as the Spring Drive system which powers the watch is totally silent, absent of the familiar tick-tock of an anchor escapement, and needed a lower noise floor.
The Security and Protections
And finally, the third innovation. The new chiming mechanism reduces the quarter-hour silence, and enables the watch’s strikes to move from striking hours to striking minutes to take place within a shorter timespan when there is no quarter hour to strike. For example, in a classical repeater, 5:05 is struck as 5 high pitched strikes, a silence the length needed to strike 3 high/low sets usually several seconds, and 5 low strikes for the minutes. In the Supersonnerie, it goes 5 high strikes, very short silence which sometimes seem to be almost absent, and then quickly followed by 5 low strikes.
And finally a security function which shields the crown from being activated for hand-setting while the repeater is striking. In a traditional repeater, moving the hands to to set the time while the repeater is striking is best left to the brave or the foolish, as the watch would often break and require a trip to the watchmaker.
First the sound. The sound is indeed as promised. Loud, clear, clean. With a beautiful decay, and an excellent tone.
Interestingly, when the watch is strapped on the wrist, it sounded even better. The intensity seemed to be amplified, and the beauty of the harmonics come through clearer. This is due to the fact that the Supersonnerie’s internal sound board is transmitting the sound through openings in the case back as opposed to the case back carrying the sound in a traditional minute repeater. The classical repeater’s case back comes into contact with the wrist, and the sound becomes muffled. But for the Supersonnerie, the Sound Board is inside the case proper and does not come into contact with the wrist, and chamber within can resonate, and propagate the sound. The case back now, becomes a board to bounce the sound off, and direct it away from the wrist. Quite amazing.
Visually, the watch is quite a spectacle. Large and imposing. The case measures 44 mm x 16.5 mm, although as the case upper is curved, the fit on the wrist is rather reasonable. The case is similar to earlier Royal Oak concepts watches, which to our eyes are a step in the right direction as a more avant garde interpretation over the traditional Royal Oak case designed by Gerald Genta or the Royal Oak Offshore case designed by Emmanuel Gueit.
Priced at a princely sum of S$ 780,000 with GST, this watch is not for the casual observer, but should be on the shortlist of those searching for the ultimate in minute repeater and/or grand complications of a sporty twist. The prospective buyer probably have already explored and owned minute repeaters from the usual suspects, viz Patek Philippe, Vacheron Constantin and perhaps even a vintage Audemars Piguets. And may be less fazzed with the high price of entry than the rest of us. But even the less economically endowed among us must pause, and applaud AP for the daring and gumption to push the limits of the age old mechanism of the minute repeater. And for the triumph they have created with their investment. For that we take our hats off. Chapeau!
The Audemars Piguet Royal Oak Concept Supersonnerie Technical specifications
Functions: minute repeater, chronograph, with tourbillon.
Case: titanium with ceramic crown and pushers, water resistant to 20m, 44 mm in diameter, with inner sealed “sound board” and case back apertures to allow sound to escape.
Movement: hand-wound caliber 2937, 29.90 mm x 8.28 mm; 21,600 bph with 478 components running in 43 jewels. Black rubber strap with AP folding buckle.
Postscript: Did we leave out the tourbillon or the chronograph. Well, sorta. But the striking system is the main draw of the Supersonnerie. The chronograph is quite standard lateral clutch controlled by a column wheel. And the tourbillon is a standard APRP (Audemars Piguet Renaud et Papi) bridged tourbillon, which admittedly is quite well executed and rather a beauty on its own.