The Grande Sonnerie boasts the title of the most complex Greubel Forsey creation to date and has now been awarded the “Mechanical Exception” prize at the Grand Prix d’Horlogerie de Genève. For eleven years, Robert Greubel and Stephen Forsey worked on the Grande Sonnerie in utmost secrecy to assemble the 935 components of this timepiece, and above all to ensure absolute harmony between the movement, the exterior and the acoustics.

The timepiece’s precision is ensured by the Tourbillon 24 Secondes, which uses fast rotational speed and an inclined angle to solve the problem of the oscillator’s critical positions in relation to gravity. The movement has a frequency of 21,600 vibrations/hour and a chronometer-worthy power reserve of 82 hours.