Personal technology is key to life today. But it has always been at the heart of Audemars Piguet. This year, the royal oak concept RD#1, a pioneering concept watch, is a passionate continuation of a complex technology that Jules Louis Audemars and Edward Auguste Piguet set out to master 140 years ago : the minute repeater system. History reveals that Audemars Piguet has been mastering sound in Le Brassus since its time began. It has never stopped

In 2015, Audemars Piguet unveils a watch that is potentially the most sonically considered minute repeater of modern times : the Royal Oak Concept RD#1, a concept watch developed according to the principles of stringed instrument making. The Manufacture’s concept watch programme was launched in 2002 and this 2015 piece adds to Audemars Piguet’s esteemed history of technological development. It is the result of over a century of innovation and a dedicated eight-year sound-research initiative. Started in 2006, Audemars Piguet has conducted this programme in collaboration with the EPFL (Ecole Polytechnique Fédérale de Lausanne). Included were a musician who crafts stringed instruments, an academic consultant from the Geneva conservatory and a sound engineer. Each responded to the research programme in different ways. The result? Royal Oak Concept RD#1 is not simply an academic exercise but a minute repeater watch that awakens sound. Today the sound research continues at a dedicated Acoustic Lab at the company’s Le Brassus manufacture.

With three patents pending, Audemars Piguet has applied the findings of this study to the Royal Oak Concept RD#1, a concept timepiece that significantly enhances the acoustic quality of horological chiming technology and that achieves an unprecedented volume of sound transmission in a water-resistant case.


Audemars Piguet, the family-owned Le Brassus Manufacture is known for its exceptional horological concepts, its independent spirit and a desire to push the limits of engineering excellence. It has been creating concept pieces since 2002 but it has been experimenting with mechanical watch technology from its inception as a Manufacture in 1875.

Customer ledgers from that time serve as a parallel history of the Le Brassus marque. These reveal minute repeater technology to be at the heart of Audemars Piguet’s offering from the start – chiming watches were most in demand back then. At the birth of the Swiss watch industry, the Le Brassus Manufacture’s passion, respect and mastery of the “king of classical complications” was recognised as exceptional.

Its chiming watches were sought out not only for their technology, beauty and craftsmanship, they were highly valued for the individual quality of their sound.

Even during the quartz crisis in the 1970s and 1980s, Audemars Piguet has continued to develop minute repeater technology and timepieces.

Now, the Manufacture’s drive to explore acoustic quality ina mechanical chiming watch has resulted in a benchmark achievement : Royal Oak Concept RD#1 is the most sonically considered concept timepiece created by a Swiss Manufacture in the digital era. Defying the necessary restrictions of water- proofing, Royal Oak Concept RD#1 breaks the rules of chiming watches by mastering sound.

Chiming watches that strike the time were a much sought-after piece of personal technology in the 1800s. The expert micro- engineers – the watchmakers of the vallée de Joux – created these luxurious personal mechanisms out of necessity : rather than having to rely on the city and pendulum clocks to tell the hour, those privileged enough to own a minute repeater pocket watch – easily placed on a bedside table – could tell the time at night via a personal time-keeper. The Royal Oak Concept RD#1 reaches beyond a watch that serves the sole enjoyment of its owner : instead, its unique sound becomes a powerful experience to be shared.

The Royal Oak Concept RD#1 is inspired by the technological quality of minute repeaters created during the pinnacle of steel gong technology during the period from 1920-1930 – just before electricity became an everyday resource. At this time, the Le Brassus watchmakers were not only considering mechanical progression but also the acoustic quality and range of chiming watches. Hence, this era has long intrigued the company’s in-house craftsmen, designers and archivists. In the process of ongoing research, they kept coming back to one piece in particular, a watch that begged the same question of each to ask : what made this 1924 minute repeater wristwatch sound so good?


The same steel gong system that Audemars Piguet used since the company was founded in 1875 is still at the heart of minute repeater technology today.

The long steel strip that curves meticulously around the movement (the gong) is worked to super strength. It requires the time- honoured skill of an experienced watchmaker so that when the gong is fully assembled, the sonic qualities of the steel are primed to achieve a harmonious tone. Filing the gongs is a meticulous task – if the steel is overworked, the tone of the chime is compromised.


The Royal Oak Concept RD#1 is ultimately inspired by those uniquely talented watchmakers who can free beautiful, clear tones from a chiming watch. It has been developed to define sonic targets for watchmakers to measure and attain the “perfect” minute repeater sound at a volume level never achieved before. In 2015, to further improve sound perception, Audemars Piguet has developed a new striking mechanism regulator that is almost silent.Without reverberation, the tone of the chiming sound is immediately brighter – it is awakened.

The Royal Oak Concept RD#1 started with an in-house laboratory research programme at the Le Brassus Headquarter of Audemars Piguet eight years ago and developed into a collaboration with the EPFL (Ecole Polytechnique Fédérale de Lausanne). The aim was to explore traditional chiming watch artistry that was naturally developed by watchmakers prior to the volume restrictions of water-proof casing. Was it possible to apply academic structure to serve as a sonic benchmark for watchmakers creating new minute repeater watches today? The Royal Oak Concept RD#1 project not only explored the possibility but achieved unique results.

The Audemars Piguet Acoustic Lab is now established as an ongoing educational exploration of sound considering how we listen and hear and how sound heightens emotional response.


So, what makes a beautiful sound? How do we define what we hear? How do you achieve pitch, tone and harmony from a minute repeater gong system? At the heart of any minute repeater sound is the watchmaker ; he is the conductor, the producer, the human element whose skill and passion brings life to a mechanical timepiece. You can’t repeat the same sound from watchmaker to watchmaker but you can give targets ; a benchmark of sound to achieve. Now, the Royal Oak Concept RD#1 has been developed using scientifically defined sonic targets for watchmakers to measure. Defying all rules, the Royal Oak Concept RD#1 offers an unprecedented minute repeater sound and volume level.


A key objective of the programme was to rediscover the sounds of the time when waterproofing was not in progress : waterproofing is a major technical restriction when engineering minuterepeaters today as the need for sealed cases muffles sound. One of the reasons watches from this period have such a beautifully considered tone is because they are not water-resistant. The sound, unrestricted is bright and clear. While researching Royal Oak Concept RD#1, the programme participants developed methods that heighten the volume in a sealed watch but that crucially,
did not compromise tone and harmony. The Acoustic Research – Episode 1 awakens sound.


The acoustic research lab studied how sound is transmitted within the functions of a minute repeater watch and now that the RD#1 study has set sound “targets”, a measure of pitch, tone and harmony becomes possible in chiming watch technology.

• Pitch : Hitting the right note
  In a watch with gongs, there are not, strictly speaking, notes. Notes are achieved through harmonics – vibration frequencies – and there is only one point of attachment – whereas with a violin, the string is attached to two parts of the instrument, enabling multiple frequencies and therefore harmonics.In watches, the equivalent is “partials”, which have no harmonics. Therefore the most important thing is not the note itself, but the relationship between two partials. For the RD#1 the partials have been redefined. A desired sound can now be targeted that is not solely dependent on how the watchmaker listens. The process of creating musical minute repeaters can now move forward.
  
  
• Tone : The color of sound
  The timbre, the richness of tone, is specific to each instrument.The construction of the RD#1 is inspired by the principles of stringed instrument making. The RD#1 study considers the hammers and gongs as the musical instrument, the movement as the musician and the watchmaker as the conductor.
  
  
• Harmony : The coming together of sounds
  Composing a piece of music requires organization – maintaining rhythm, harmony and pitch all at once. The RD#1 study considered the harmony between two partials, to try to achieve something equivalent to a major third – a perfect interval of two notes. A musician with perfect pitch was called in to help achieve the desired harmonies.
  
  
• Time :The length of sound
  The persistence – or sustain – of sound, like a bell that resounds for a longtime, is different for each “note” (partials). The note “A” was set as the keynote to achieve for RD#1. The gong system has been adapted so that somepartials last longer than others. A new striking mechanism regulator has beenengineered to strike at the right time without an unwanted reverberation or 19 echo : the sound of the regulator does not sustain.

Several key rules were devised during the RD#1 research processin an attempt to get as close to the high-quality sounds of antique watches and to further understand the acoustic rules of the human ear. Also considered was the intelligibility of sound, the meaning that we give to sound, why certain sounds are heard and others not.

The RD#1 is a significant development in Audemars Piguet’s rich history of creating unique concepts. In 2015, the Le Brassus Manufacture has fully explored the potential of chiming sound, while never losing sight of the natural pleasure we derive from listening to it.