After exploring the tourbillon, and improving on it in all aspects (by adding inclination to the cage, by using not one, but two or even four of them or by changing the usual one-minute rotation to a faster 24-second cycle), it was time for Greubel Forsey to focus their mechanical creativity on something different… The choice was made to give a new vision of one of the most traditional complications, the Perpetual Calendar. Launched 2015, the Greubel Forsey QP à Equation now receives a new Rhodium-Coloured Gold Dial.
Back in 2015, Robert Greubel and Stephen Forsey decided that it was time for the company to move in new directions and to explore different horological complications other than their signature tourbillon(s). While they already had a complex GMT watch in their catalogue, the choice was made to look at what certainly best represents the Haute-Horlogerie, the perpetual calendar. Complex but very well-known, the question was: how to redefine, how to reinvent one of the most widely used features of the HH? The Greubel Forsey QP à Equation is a perpetual calendar with an equation of time, à la Greubel, meaning it’s not just a ‘simple’ QP.
Dial-side, all the calendar indications of the Greubel Forsey QP à Equation are located in a small area at 4 displayed by 3 apertures – one for the day, one for the date and one for the month. Highly legible and intuitive, the display could be seen as simple, but in fact, it is Greubel Forsey’s 7th invention, the “Computer Mecanique”. Under the circular area that comprises these indications (and also visible on the back-side, with the equation of time) is a mechanical brain. This sub-assembly comprises 25 parts, mainly consisting of rotating coaxial coded elements in an arrangement complemented by a system of programmed movable sections. Depending on its geometry and speed of rotation, each element generates its own indication in a cyclical, preprogrammed way. In the context of the QP à Equation, the Mechanical Computer is programmed to automatically display all the indications of the perpetual calendar through to the equation of time: the seasons, the equinoxes, the solstices, the equation of time, and the date, day, month and the four-digit year.
Another major improvement concerns the adjustment of these calendar indications. It is known that traditional QPs are sensitive mechanisms that can easily break or block if adjusted wrongly. On the Greubel Forsey QP à Equation, all the indications can be adjusted both forwards and backwards via the crown (meaning no unsightly pushers or recessed buttons in the casebands), at any time of the day. Finally, as always at Greubel Forsey, the movement of the QP à Equation is finished and decorated in an uncompromising way – it’s certainly one of the most detailed decorations of the entire industry.
The rest of the movement isn’t to be left behind, as the regulation is done by a 24-second inclined tourbillon (the 25° angle and the rapid revolution of the tourbillon cage significantly improve the chronometric performance) and the power reserve is 72 hours. The display of this QP à Equation, as always with Greubel Forsey, is somehow “exploded”: hours and minutes in the centre, small second below the tourbillon, calendar indications at 4, leap year at 6, power reserve at 2 and the 24 hours of the day and night the small disc next to the small second). More indications can be seen on the movement side: the equation of time (two sapphire crystal discs driven by the Mechanical Computer which rotates them independently to show the time difference as it changes throughout the year) as well as the year, displayed with 4 digits.
For 2017, the Greubel Forsey QP à Equation receives a new face, with a Rhodium-Coloured gold dial (in addition to the anthracite version). The case is the same, in white gold and with a 43.5mm diameter and a 16mm height. This new Rhodium-Coloured version of the Greubel Forsey QP à Equation should be priced equally to the previous anthracite model, meaning CHF 670,000 (before taxes). More details on www.greubelforsey.com.
Technical Specifications – Greubel Forsey QP à Equation
- Case: 43.5mm diameter x 16mm height – 18k white gold, polished and brushed – Sapphire crystal on both sides – 30m water resistant
- Movement: in-house calibre – hand-wound – 624 components – tourbillon 24-second inclined with 3Hz frequency – 72h power reserve with 2 barrels – 75 rubies
- Display: Hours, minutes, small second, power reserve, QP with day, date, month, leap year, day/night indication, indication of the function selected, equation of time, year on 4 digits
- Strap: black alligator with 18k white gold folding clasp
- Price: CHF 670,000 before taxes