Insider: Greubel Forsey Grande Sonnerie. Hands-on with the Most Impressive Timepiece from Greubel Forsey So Far.

One of the most impressive timepieces we've ever reviewed and the very first time we got to play with a Grande Sonnerie watch, please meet the new Greubel Forsey Grande Sonnerie, an exceptional timepiece that took 11 years of Research & Development and that combines a Petite and Grande Sonnerie with a Tourbillon in one watch. This is by far, one of the three most impressive watches presented at the SIHH 2017. Composed of no less than 935 parts in addition to the filling of two patents, the development of an acoustic resonance cage producing an extremely pure sound like this one was a true feat for the team at Greubel Forsey. A timepiece that incorporates eleven security functions ensuring maximum peace of mind for the user, the new Grande Sonnerie is not only Greubel Forsey's first Grande Sonnerie, but also one of the very few brands in the world that proud themselves on creating one.

The Case

Water resistant to a depth of 30 meters, the new Greubel Forsey Grande Sonnerie is cased in a titanium case measuring 43.5 mm in diameter and 11.13 mm in thickness. The new Greubel Forsey Grande Sonnerie is ergonomically designed for perfect wearability and its case combines a satin brushed finish on the caseband with highly polished lugs, bezel and case back. Additionally, a small lateral curved sapphire crystal window is located to the left of the left lug at 6 o'clock to allow for a side view of the inclined tourbillon and the black polished steel gongs. A big difference between this watch and other Grande Sonnerie timepieces is that Greubel Forsey decided to use a pusher instead of a lever to select the different modes on the watch from Petite Sonnerie —strikes the full hours in passing— to Grand Sonnerie —striking the hours and quarters in passing— and a convenient silent mode where the hammers don't strike at all. Additionally, the crown is fitted with a pusher on its center that allows for the minute repeater to be operated on demand.

The Dial

In good old Greubel Forsey fashion, the new Grande Sonnerie is fitted with the traditional multi-level dial construction. The gold dial in matte black color, features an array of elements with different indications on it. First, between 1 and 2 o'clock there is a sector power reserve indicator for the Grande Sonnerie mechanism, then right below it, there is a Sonnerie selector indicator that shows whether the Petite Sonnerie, the Grande Sonnerie or the Silent Mode have been selected.

At 8 o'clock an opening gives full view of the tourbillon at a 25 degree inclination and which performs a full rotation every 24 seconds. Next to it, there is a running seconds indicator and to its right around 5 o'clock, a 72-hour power reserve indicator for the watch mechanism.

At 11 o'clock an opening shows the black polished striking hammers that strike the cathedral gongs. Capitalizing on the principle of multi-level construction and architectural balance, every component and indication on the dial side is executed flawlessly.

The Movement

For this feat of horology and Greubel Forsey’s most complex creation to date, the manual wound movement powering this timepiece is equipped with two winding mechanisms, a manual wound one for timekeeping and for the tourbillon, and then a second automatic winding mechanism for the striking mechanism —with a 20-hour autonomy in Grande Sonnerie mode when fully wound.

Composed of 855 parts and 86 parts for the tourbillon cage with a total weight of mere 0.37 grams, the movement features the traditional olived-domed jewels in gold chatons that Greubel Forsey is very well know for —a total of 85 in this movement. Thanks to two coaxial series-coupled fast rotating barrels, the Greubel Forsey has a power reserve of 72 hours when fully wound while beating at a frequency of 21,600 vph.

The oscillating weight for the automatic winding of the striking mechanism is made of platinum and features a relief-engraving of the GF texts with flat black polished gold central plate with GF logo and gold peripheral plate with lacquered 'Grande Sonnerie' on it.

Making this movement even more impressive, the decoration of the bridges is simply remarkable. The tourbillon bridge and the bridge next to it feature relief-engraved text, with polished beveling and countersinks, straight-grained flanks and a screwed gold chaton. In all, this movement is simply breathtaking and one of the most fascinating movements we've ever seen in person.

On the Wrist & Pricing

On the wrist, the new Greubel Forsey Grande Sonnerie is simply out of this world and an exceptional timepiece from top to bottom. For this particular timepiece, we find ourselves short on words to explain the amazing feeling and the emotions that come along with strapping a timepiece of this caliber to one's wrist.

Without a doubt, one of the most impressive and special watches we've had the pleasure to review and feel on our wrist. Regarding the sound from its cathedral gongs, there is no recording that can accurately reproduce the actual sound of it in person and what we felt when we heard its glassy harmonious notes.

Big Kudos to Greubel Forsey for working so hard on this new timepiece that is pure love for horology.

Sticker Price CHF 1,150,000 —approximately $1,165,000 USD. For more info on Greubel Forsey click here.