Patek Philippe has been in the hands of the Stern family since 1932. Third generation Philippe Stern led the company from 1993 until 2009, when his son Thierry took the helm as president.
The 85th birthday of Philippe Stern is marked by the Minute Repeater Alarm powered by a new movement developed solely for this 41mm platinum timepiece.
The honorary president appears in a miniature painting on the Grand feu black enamelled dial. His year of birth is indicated in the reference number 1938P-001.
Thierry Stern further pays tribute to his father through the hand-engraved inscription "A mon père, 85 ans de passion horlogère" on the hinged dust cover of the caseback.
With its straight lugs and screwed-in strap bars, the case recalls the officer-style Ref 3960 launched on the occasion of the company's 150th anniversary in 1989. The milestone was also marked by Philippe Stern's revival of wrist-worn minute repeaters.
Founded in Geneva in 1839, Patek Philippe became a virtuoso of chiming watches, whether those that strike automatically "in passing" (grande sonnerie, petite sonnerie) or those that strike on demand (repeaters).
An engraving reproduces Philippe Stern's signature on the rotor of the movement.
Platinum was chosen as the case material for the commemorative Reference 1938P-001 in order to acoustically obtain the "Patek Philippe sound".
Like other platinum timepieces made by the independent watchmaker, the limited edition of 30 pieces is characterised by a diamond set into the caseband at 6 o'clock.
Engineering the new movement meant rethinking the minute repeater mechanism to accommodate the alarm.
The challenge was to make the minute repeater and the alarm chime on the same two classic gongs while retaining the system of a slide piece set into the left flank of the case, a visual signature of Patek Philippe's minute repeaters.
The push-piece integrated into the crown serves to select the chiming mode, which is displayed in a small bell-shaped aperture at 3 o'clock. The bell is black, red and white to respectively represent the minute-repeater, alarm and alarm actuated modes.
The 12-hour programmable alarm time is set from one quarter-hour to the next by means of the crown pulled out to the middle position and the rose gold hand pointing to the scale on the periphery of the dial.
To allow the maximum number of chimes to be heard, the alarm always strikes two minutes before the programmed time. Accordingly, if the alarm has been set for 3 o'clock, the watch will sound two low-pitched strikes, three double high-low strikes and 13 high-pitched strikes, making 21 strikes in total.
Four new patents were required to develop the Calibre R AL 27 PS, which will never equip any other watches again.
The sapphire crystal reveals the self-winding movement, whose yellow gold mini-rotor is adorned with a black-lacquered hand engraving reproducing Philippe Stern's signature.