At the SIHH 2017 Greubel Forsey will officially present its most complicated creation so far. The exceptional model dubbed Greubel Forsey Grande Sonnerie consists of 935 individual components. It took 11 years of research and development for the Swiss manufacturer to join the club of watch manufacturers that offer a grande sonnerie complication.
A Grand Sonnerie is a very rare complication, featuring a chiming mechanism that strikes on its own every hour, repeats hours and indicates quarters at each quarter-hour. For instance, it is much more complex than a minute repeater which chimes hours, quarters, and minutes only on demand. Therefore, it is such a challenge for the most watch maisons and only a few watchmaking brands in the world have the expertise to make it.
In order to keep the watch light as possible, the Swiss watchmaker housed it in a titanium case measuring 43.50mm in diameter and 16.13mm in thickness. The titanium case also provides that the chimes sound more clear and vibrant.
The beating heart of this exquisite timepiece is the hand-wound movement with patented tourbillon, and patent-pending full striking-mechanism with automatic winding. In other words, the Greubel Forsey Grande Sonnerie comes with a separate power supply for the timekeeping part of the timepiece (giving it a 72-hour power reserve), as well as for the chiming mechanism. The latter is powered by the mechanism on a platinum rotor which can be admired from the back of the case. It provides a 20-hour power reserve for the watch whilst it is in grande sonnerie mode.
Underneath the front sapphire glass lies a multi-level, black-coated gold dial comprising an aperture between 10 and 12 o’clock position showing the hammers and gongs of the chiming mechanism, a chiming mode indicator located at the 3 o’clock position, a small seconds counter on a sector bordering the tourbillon aperture, a power reserve display for the grande sonnerie set at the 2 o’clock position, as well as yet another power reserve indicator placed at the 5 o’clock position. The hands and hour markers are crafted from gold. The same material has also been used for the crown which incorporates the pusher for the chimes.
The Grand Sonnerie by Greubel Forsey is delivered with a hand-stitched alligator leather strap, fitted with a titanium folding clasp. The watch will be issued in the ultra-limited series of only five to eight pieces per year. The retail price will be 1,150,000 Swiss francs.