The engineers at Patek Philippe Advanced Research have extended the horizon of its chiming watches by developing a totally new all-mechanical sound amplifying system. This fortissimo “ff” module consists of a flexibly suspended sound lever and an oscillating wafer made of transparent sapphire-crystal glass.

Crowned by four patents, the pioneering technology is presented in the Ref. 5750 Advanced Research minute repeater, a special limited edition consisting of 15 watches cased in platinum and endowed with a unique dial design.

The spirit of innovation has been in Patek Philippe’s DNA since the company was founded. Since 2005, Patek Philippe Advanced Research has stood out with pioneering work in the innovative field of Silinvar, a derivative of silicon with phenomenal characteristics for watchmaking applications (temperature compensating, lightweight, lubricant-free, antimagnetic, etc.).

Departing from the famous self-winding caliber R 27, the movement with which Patek Philippe in 1989 ushered in the grand comeback of the minute repeater, 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 manner while preserving the excellent acoustic quality as well as the smallest possible dimensions.

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 in this specific case improves the quality of the strike in line with the directives of the Patek Philippe Seal and produces a softer strike as well without reducing its sonority.

In its center, the five-part elaborately constructed dial features an open-worked motif inspired by the spoked wheels of vintage automobiles. It stands out against the black background with snailed spiraling lines. The time is indicated by flat Dauphine hands in white gold and applied kite-type hour markers in blackened white gold.

The open-worked motif of the sapphire crystal case back

The sapphire-crystal case back reveals the hammers and the classic gongs of the minute repeater a well as the sound lever in the shape of a tuning fork that carries the transparent oscillating wafer of the fortissimo amplifier system. A pierced Calatrava cross decorates the cover of the centrifugal governor that assures the regular rhythm of the time strikes.