Exploring Caliber GS 36-750 PS IRM

To implement the grande sonnerie as envisioned by Patek Philippe, a new movement was created using an adpation of the caliber 300 of the Grandmaster Chime. The new, 703-part caliber GS 36-750 PS IRM features six complications, a strikework with three classic gongs and was granted three patents.

Explore its movement in glorious detail.

The grande sonnerie automatically strikes the full and quarter hours, complemented with a petite sonnerie which does not repeat the hours before the quarter strikes, a minute repeater which strikes on demand, and with patented jumping subsidiary seconds.

One of the greatest difficulties for the engineers of grande sonnieres is mastering energy flows and power reserves, as the grand sonnerie needs to have sufficent reserve power to automatically sound the required time with uniform acoustic quality.

To implement the grande sonnerie as envisioned, Patek Philippe developed a new movement using an adpation of the caliber 300 of the Grandmaster Chime, and introduces the new manually-wound caliber GS 36-750 PS IRM.

Given its 703 parts and 95 jewels, the calibre is remarkably compact for such a complex mechanism (diameter: 37 mm; height: 7.5 mm).

The strikework consists of three classic gongs – low, medium and high. This technical option requires more energy than systems with two gongs.

It also complicates the watchmaker’s work when tuning each gong until all three create the legendary “Patek Philippe sound” so coveted by connoisseurs.

The six complications of the Grande Sonnerie ref. 6301P: Grande sonnerie. Petite sonnerie. Minute repeater. Movement power-reserve indicator. Strikework power-reserve indicator. Jumping seconds.

The three patents granded for the caliber GS 36-750 PS IRM: Isolation of the grand sonnerie in silence mode. Selection of the strikework mode. Jumping display with a jumping second wheel.