At the 2014 edition of the SIHH, Greubel Forsey exhibited a new perpetual calendar called the QP à Équation. See Give Me Five! Perpetual Calendars.

Perpetual calendars seemed to be in the haute horlogerie air in 2014, and the trick is obviously for brands to find ways to make them interesting, clean, and diverse. To be honest, there was hardly a quantième perpétuel that better fit that bill in 2014 than Greubel Forsey’s QP à Équation with its clear legibility and easy mode of operation.

Greubel Forsey Quantieme Perpetuel with bi-directional setting and equation of time

For example, most perpetual calendars need to be set and adjusted using a number of pushers recessed into the case, accessible only with a stylus. Here, all functions can be set and adjusted via the crown, making it as easy to use as a simple date display.

Another perennial weak point of perpetual calendars has been that the many displays can look a bit messy, making it hard to find the right information at a glance. Greubel Forsey thought that one out, too: the day, date and month are displayed linearly on the dial at the 5 o’clock position (a balanced opposite to the 25-degree inclined 24-second tourbillon). Information needed less frequently – such as the equation of time – is found on the back.

The “Manta Ray” shape display of the equation of time on the back of the Greubel Forsey QP

The equation of time basically displays the difference between mean and solar time, which can vary up to 16 minutes on a given day. This is displayed by two cleverly superimposed transparent disks crafted in sapphire crystal.

And it is this back display that has delayed the final introduction of this beautiful example of high-end watchmaking. Robert Greubel, being the perfectionist he is, was still not quite 100 percent happy with it after the fair and has taken some time to tweak it to perfection. What you now see is Greubel’s idea of perfection, and I think we would all agree that it was worth the wait.

Greubel Forsey Perpetual Calendar with Equation of Time

The seventh invention

Another interesting thing about the QP à Équation is that it contains Greubel Forsey’s seventh invention, a subassembly of 25 components for which several patents have been filed. Partially inspired by systems from large astronomical clocks of the fifteenth century, the subassembly is basically an information manager for key calendar dates.

Greubel Forsey calls this invention the Computeur Mécanique (“mechanical computer”), and it is a mechanical “brain” containing coded elements and programmed, moving sections. Each of its elements is construed to generate its own indication in a cyclical way.

Now miniaturized and applied to the movement of the QP à Equation, it adapts the proven theoretical concept of the Mechanical Computer to control functions and calculations of multiple indications and then integrate them within the caliber so that is can present the numerous displays in a cohesive manner: seasons, equinoxes, solstices, day, date, month, four-digit year and, of course, the equation of time.

GMT Black by Greubel Forsey

Greubel Forsey GMT Black

GMT goes color: black and gold

Since its introduction at the 2012 edition of the SIHH, the Greubel GMT has managed to establish itself as a mechanical delicacy of the most collectible type. In my humble opinion, the three-dimensional globe placed at 8 o’clock on the front of the watch is not only perhaps the most interesting focal point of this timepiece, but a premium example of the graphic way a world time watch can look when a master of detail like Greubel Forsey gets its hands on it.

Greubel Forsey GMT with red gold dial

At the SIHH, two new examples of this popular timepiece have been introduced: one in a black ADLC-treated (ADLC standing for amorphous diamond-like carbon) case, and one boasting a red gold finish on the plates and bridges. The rich, rusty tone contrasts beautifully with the platinum case and black dial elements.

Greubel Forsey GMT Black on the wrist

Greubel Forsey GMT with platinum case and red gold dial

Both the platinum/red dial and black GMT models are limited to just 22 pieces worldwide.

Tourbillon 24 Secondes Vision by Greubel Forsey

Tourbillon 24 Secondes Vision

With the all-new Tourbillon 24 Secondes Vision, Greubel Forsey has turned the concept of asymmetric cases 90° so that rather than having a protrusion on the caseband, here there is a dome the display back housing the inclined fast-rotating 24-second tourbillon.

Asymmetric case protrusions allow for a smaller-diameter case than would otherwise be the necessary, while the bubble on the display back of the Tourbillon 24 Secondes Vision allows for a thinner case. And the watch is surprisingly comfortable on the wrist.

Dome housing the 24-second tourbillon on the back of the Greubel Forsey Tourbillon 24 Secondes Vision

The dial looks clean with little embellishment, however closer inspection reveals myriad sophisticated details. The heat-blued hands have been pared back to the minimum and are extremely fine. The numerals and indices around the chapter ring and small seconds are oven fired enamel: they have been engraved in the 18K gold dial, filled will enamel and fired multiple times, then the gold dial has been silvered.

Dome housing the 24-second tourbillon on the back of the Greubel Forsey Tourbillon 24 Secondes Vision

And then there’s that stunning mirror polished tourbillon bridge arcing over the regulator, the wide design quite distinct from the brand’s previous tourbillon bridges. The Tourbillon 24 Secondes Vision is a unique edition of 22 pieces in white gold.

Greubel Forsey Tourbillon 24 Secondes Vision on the wrist

Greubel Forsey Tourbillon 24 Secondes Vision

For more information, please visit www.greubelforsey.com.