Greubel Forsey Différentiel d’Égalité & GMT Earth

Greubel Forsey presented three new timepieces at SIHH 2018. However, in fact, only one is fresh. The other two problematic are the new iterations of the watches that already exist in their series.

Différentiel d’Égalité
We will start with the new kid on the block, Différentiel d’Égalité, which features the fifth invention of Robert Gaupper and Stephen Fauci.

As early as 2008, Greubel Forsey announced at Baselworld that they had figured out a way to use a spherical differential to provide a stable mainspring for the balance wheel Energy transfer rate without considering the torque along the drive chain.

Its way to achieve this constant energy dissipation is to install an auxiliary spring on the differential, after the main spring, to adjust the energy transfer. The secondary spring can be reloaded every five seconds to adjust and maintain a constant energy transfer rate. This is the fifth invention of Greubel Forsey . replica wholesale

Ten years later, the fifth invention, which was only a proof of concept at the time, was finally put into production scale timepieces with a lot of improvements. For example, the secondary spring now restarts every second, thereby forming a mechanism that can maintain a larger and more regular regulation of energy dissipation. Reloading every second also created the opportunity for Koppelfors to produce the first timepiece without jumping seconds.

The timepiece is also equipped with a 30° tilting balance wheel from Koppelforth. The balance wheel is equipped with a stop mechanism that can be used when you pull out the crown to adjust the time. When the crown is pulled out, the second hand will also return to zero by itself, so you can set the time on the watch more accurately.

Greubel Forsey Différentiel d’Égalité will use a 44 mm white gold case.

Greenwich Mean Time Earth
Next is the Greenwich Mean Time Earth. You must be wondering what makes GMT Earth different from Greubel Forsey GMT. This answer can be found on the back of the new watch and is related to the 3D globe at 7 o’clock.

You will see that in Greenwich Mean Time, a titanium globe that rotates on a 24-hour scale every 24 hours can only see its northern half. Now with the Earth in Greenwich Mean Time, the entire planet is visible, thanks to some ingenious sapphire crystal designs.

The remaining original functions of GMT remain unchanged: hours and minutes; small seconds; 72-hour power reserve indicator; GMT time indicator and 24-time zone universal time indicator are visible through the bottom cover. The watch also retains a 24-second tourbillon tilted 25°.

The Greubel Forsey GMT Earth watch uses a 45.5 mm white gold case.

Double balancer
The last piece comes from SIHH 2016: double balancer. Of course, when we first saw it, this watch was white gold and had a silver-plated gold dial. The 2018 timepiece now uses a 43 mm 5N red gold case with a black multi-layer gold dial with engraved and oven-baked hour markers.