Patek Philippe - Ref. 5750P Advanced Research Fortissimo

Patek Philippe launched the new Patek Philippe Ref. 5750P Advanced Research Fortissimo minute repeater. Full specs and price: CHF590,000.

Patek Philippe is introducing today a new all-mechanical sound amplifying system developed by the engineers of its “Advanced Research” department and consisting in a flexibly suspended sound lever interacting with an oscillating wafer made of transparent sapphire-crystal glass.

In comparison with conventional minute repeaters and regardless of the case material, this Fortissimo “ff” amplifier module delivers clearly amplified sound of excellent acoustic quality. 

Protected by four patents, this technology is for the first time presented in the new Ref. 5750 “Advanced Research” minute repeater, a special edition limited to just 15 watches housed in 40 mm x 11.1 mm case machined from a single piece of 950 platinum with a slide for actuating the minute repeater on the left caseband. 

Founded in 2005 and currently integrated in the Research & Development division, the Patek Philippe “Advanced Research” department pursues high-end research in the fields of new materials and technologies also collaborating with independent external research facilities such as the Centre suisse d’électronique et de microtechnique de Neuchâtel (CSEM) or the Federal Institute of Technology Lausanne (EPFL).

Using the self-winding caliber R 27 introduced in 1989 as the starting point, the engineers and designers at Patek Philippe “Advanced Research” searched for a way to amplify the volume of the time strike in a purely mechanical way while preserving the excellent acoustic quality as well as the smallest possible dimensions. 

While preserving the design of the base movement, they added a module that works like a mechanical loudspeaker on the bridge side (the side facing the wrist).

In order to amplify the sound, instead of using a membrane, the new patented Patek Philippe system has an oscillating wafer made of synthetic sapphire with a thickness of 0.2 mm. Thanks to its angular motion, this rigid and freely movable wafer provides clearly better sound propagation for the confined volume of a wristwatch. 

The transparency of the sapphire glass also makes the movement visible through the case back. 

To achieve sound transmission from the gongs of the minute repeater to the sapphire-glass oscillating wafer, the engineers developed a system with a steel sound lever that is attached in the middle of the oscillating wafer. 

The other end of this sound lever that resembles a tuning fork features a flexible attachment with a thickness of 0.08 mm. When the hammers strike the gongs, their oscillations are transmitted to the sound lever which in a first phase amplifies them and transmits them to the rigid oscillating wafer where they are further amplified. The angular motion of the oscillating wafer excites the air layers above and beneath the sapphire glass, producing a noticeably louder sound.

A pierced Calatrava cross decorates the cover of the centrifugal governor that assures the regular rhythm of the time strikes. 

Together with the integration of the fortissimo “ff” amplifier module, the Advanced Reasearch team also developed a new sound propagation system. In most minute repeater watches, the strikes of the hammers on the gongs create oscillations of the entire watch with the sound being propagated on all sides by the case, the back, and the crystal glass. For this reason, the case material significantly affects the sound  the resulting sound. In the minute repeater with the fortissimo module, an insulation rim made of a high-tech composite material acoustically uncouples the amplifier from the movement. 

The sound is first routed to the sound lever and then to the oscillating wafer and subsequently propagated through four openings at 12, 3, 6, and 9 o'clock in a titanium ring. The sound waves exit through a narrow slot between the case back and the case band. 

A dust filter made of a nylon polymer  (the same type that is also used in mobile phones to protect them from humidity and dust) protects the movement without affecting the sound. As it is easy to imagine, the watch is not water-resistant but protected against moisture and dust.

Thus, the case material does not influence the sound and its propagation. With this unique approach, a case crafted from platinum - the most challenging material for a chiming watch due to its density - can offer the same sound quality of a gold or titanium one. It was for this reason - to demonstrate the efficiency of the fortissimo system - that Patek Philippe decided to use 950 platinum for the case of this reference.

The fortissimo module attached in the case back allows the sound to be heard at a six-fold larger distance. So a classic minute repeater on the wrist, at a distance of 10 m, sounds as loud and clear as an amplified minute repeater at a distance of 60 m. 

Apart from the additional fortissimo module, the caliber R 27 PS benefits from further technical enhancements with respect to materials and design factors. The minute repeater hammers, originally in steel, were replaced with platinum hammers, a patented solution that produces a softer strike  without reducing its sonority. To deliver the same winding power with a thinner design, the eccentrically recessed minirotor in 22K gold was replaced by a minirotor in platinum.

Featuring the Gyromax balance spring in Silinvar launched in 2006 by Patek Philippe “Advanced Research”, the self-winding Caliber R 27 PS beats at the frequency of 21,600 vibrations per hour (3 Hz) with a power reserve of 43 to 48 hours.

The five-part dial features an openworked motif inspired by the spoked wheels of vintage automobiles. It stands out against a black background with snailed spiraling lines. 

The subsidiary seconds at 6 o'clock consists of a rotating disc with the same openworked motif against a black snailed background and a small marker serving as a hand. 

Flat Dauphine hands in white gold and applied kite-type hour markers in blackened white gold complete the ensemble.

  

Matched to a shiny orange alligator strap with black contrast seams and a platinum fold-over clasp, the new Patek Philippe Ref. 5750P Advanced Research Fortissimo has a price of CHF 590,000. patek.com