In a move that will no doubt please their core collector base, Patek Philippe today introduced a new chiming watch, the Ref. 6103P Grand Sonnerie. The venerable watchmaker’s latest combines a grand sonnerie, a petite sonnerie, a minute repeater, and a jumping seconds indication in a surprisingly slim and modern package.

The Patek 6103P Grand Sonnerie has a glossy grand feu enamel dial

Much of its technical underpinnings derive from the Ref. 5175R Grandmaster Chime introduced in 2014 to mark the 175th anniversary of the brand. Patek calls this the “purest manifestation” of the grand sonnerie complication. The grande sonnerie, if you recall, is a chiming complication that automatically strikes the full hours and the quarter hours in passing. The petite sonnerie strikes the hours and quarters in passing without repeating the hours at each quarter, while the minute repeater strikes on demand.

The recessed case flanks have a satin-brushed finish

The watch uses a 44.8 platinum case that is just 12 mm thick, quite a feat indeed given the complexity of the movement it hides. The case is fitted with a concave bezel and has satin-finished flanks, and as is wont for all of their platinum watches, a diamond is set at 12 o’clock. The glossy black grand feu enamel dial has white gold applied Breguet numerals and time in indicated by white gold leaf-shaped hands. A subsidiary jumping seconds indication is seen at 6 o’ clock and curved power reserve indicators for the going train and the chiming function. The pusher of the minute repeater is integrated into the crown and a slide switch to toggle between the chiming mechanism modes is placed on the case flank at the 6 o’ clock position.

The use of Super-Luminova is a concession to modernity

The manual-winding Caliber GS 36-750 PS IRM as mentioned earlier derives from the Caliber 300 of the Grandmaster Chime. Much to their credit, the development team has been able to confine the movement’s 703 parts within a 37-mm-wide, 7.5-mm-thick space. To manage efficient energy transmission, especially on the chiming mechanism, the engineers connected two twin mainspring barrels in tandem. The going train that indicates for the conventional time indication is connected to a mainspring that has a 72-hour power reserve. The chiming function has a 24-hour power reserve thus allowing it to strike the full hours and the quarter hours during an entire day with equal intensity. Rotate the crown clockwise to wind the going train and counter clockwise to wind the chiming unit.

The striking mechanism uses three gongs

The striking function uses three gongs as opposed to two in lesser watches; the hours are struck on a low-pitched gong, the quarter hours with a three-strike high-low-medium sequence. The melody for the first quarter hour (15 minutes) sounds once, for the second quarter hour (30 minutes) twice and for the third quarter three times. Each quarter-hour sequence is automatically preceded by the number of elapsed hours, and followed by the number of quarter hours. During the duration of an entire day, the chiming mechanism executes 1056 strikes.

As mentioned earlier, the patented sonnerie slide – to switch between the grand sonnerie mode and the petite sonnerie or completely disengage the chiming mechanism is – is placed on the case flank at 6 o’clock. In petite sonnerie mode the watch chimes the full hours but omits the repetition of the hours when striking the quarter hours. In the silence mode, the automatic time strike is switched off altogether. Another patent, also developed for the Grandmaster Chime, allows the complete isolation of the grande sonnerie in the silence mode, eliminating power consumption.

The manual winding Calibre GS-36-750-PS IRM

The jumping seconds mechanism of the subsidiary dial was borrowed from the Ref. 5275 Chiming Jump Hour, another timepiece made to celebrate the 175th anniversary. This mechanism, also patented, does not rely on jumper springs but instead with wheels and a release lever that instantaneously unblocks the wheel train every second, making energy consumption easier to regulate and control.

There is some cutting-edge 21st century technology thrown into the mix too. The movement uses Patek’s free sprung Gyromax balance and a Spiromax balance spring in Silinvar (Patek’s proprietary silicon alloy). The sapphire crystal caseback ensures that we get to see the striking mechanism and the refined architecture of the movement. The timepiece is paired with a hand-stitched black alligator strap with square scales and a fold-over clasp.

Due to the complex nature of the movement, only a few pieces will be produced each year. The watch is priced at CHF1.25 million.