The Greubel Forsey Quadruple Tourbillon Secret watch evokes to the passionate enthusiast the promise of an exceptional movement in which a magical mechanical ballet plays out on a hidden stage visible only through the display back. The dial side redefines the expression of telling the time with its harmonious arrangement of multiple dials.
Ultra-exclusive, the Quadruple Tourbillon Secret comes in a unique edition of eight pieces in 5N red gold and eight pieces in platinum.
The ultimate in refinement, the ballet of the tourbillons is visible only through the synthetic sapphire crystal display back. This private micro-mechanical performance becomes a witness to the bond that unites the owner with the values of Greubel Forsey. A bond further strengthened by the precious exclusivity of the Quadruple Tourbillon Secret.
This timepiece houses Greubel Forsey’s second fundamental invention, the Quadruple Tourbillon: a reliable high-performance mechanism comprising four tourbillons configured in independent pairs, which are linked by a spherical differential that averages out any timing errors between the two regulators. Particularly in stable positions, timekeeping accuracy is improved by the Quadruple Tourbillon.
The movement comprises 519 components of which 261 make up the four tourbillon cages and is powered by two mainspring barrels which provide an effective power reserve of 50 hours. The oscillators feature variable inertia balance wheels, Phillips terminal curves and beat at 3Hz/21,600 APH.
The plates and bridges are in nickel silver finished in nickel-palladium with straight-grained and spotted finishes and hand polished bevels. The dials are in blackened or silvered gold with applied indices.
The case is available in platinum 950 or 5N red gold and measures 43.5 mm in diameter by 16.11 mm high and features asymmetrical domed synthetic sapphire crystals on the dial side and for the display back.
The black alligator strap is hand stitched with a folding clasp in platinum 950 or 5N red gold to complement the case.
Technical details
Model: Greubel Forsey Quadruple Tourbillon Secret
Edition
Unique edition of 8 pieces in platinum and 8 pieces in 5N red gold
Movement
Mechanical hand-wound movement, Calibre GF03j
Quadruple Tourbillon • power-reserve indicator• hour and minute display • small second • 4-minute outer tourbillon rotation indicators.
Movement with patented tourbillon
Movement dimensions
• Diameter: 36.40 mm
• Thickness: 9.85 mm
Number of parts
• Complete movement: 519 parts
• 4 tourbillon cages: 261 parts
• Total weight: 2.35 g
• Spherical differential: 28 parts
Number of jewels
• 63
• Olived-domed jewels in gold chatons
Power reserve
50 hours
Barrels
Rapid rotating twin barrels (1 turn in 3.2 hours) one of which is equipped with a slipping spring to avoid excess tension
Balance wheel
Free sprung variable-inertia balance with white gold mean-time screws (10.70 mm diameter)
Frequency
21’600 vibrations/hour
Balance spring
• Phillips terminal curve
• Geneva-style stud
Main Plates
Nickel silver, spotted with polished bevelling, straight-grained flanks, black ruthenium treatment (18k 5N red gold version) or nickel-palladium treatment (platinum 950 version)
Bridges
• Nickel silver, frosted, spotted with polished bevelling, black ruthenium treated (18k 5N red gold version) or nickel palladium treated (platinum 950 version)
• Gold nameplate engraved with the individual number
• Two steel Tourbillon bridges (movement side): hand-bevelled, flat black polished with polished countersinks
• Two nickel silver Tourbillon bridges (dial side)
Gearing
• Involute circle profile
• Conical gearing with corrected profiles
Inner Tourbillons
Inclined at a 30° angle, 1 rotation per minute
Outer Tourbillons
• 1 rotation in 4 minutes
• Hand-bevelled and open-worked cage pillars
• 1 gold counterweight per double cage
Displays
Hour and minute
Small second (mean performance)
50-hour power reserve on a sector
4-minute outer-tourbillon rotation indicators
Exterior
Case
Case material: 18k 5N red gold/ platinum 950
Diameter: 43.50 mm
Thickness: 16.11 mm
Asymmetrical convex sapphire crystal
Transparent back with asymmetrical convex sapphire crystal
Lateral window with shaped sapphire crystal
Three-dimensional, variable geometry-shaped lugs
Gold security screws
Polished bezel and centre band with hand-finished straight graining
Hand-engraved individual number
Raised polished engraving “Quadruple Tourbillon” on a hand-punched background
Water resistance of the case: 3 atm – 30 m – 100 ft (standard NIHS 92-20/SN ISO 22810:2010)
Crown: In platinum with engraved and black lacquered GF logo
Dial
Silvered dial
Gold hour markers
Gold display sectors
Applied gold GF logo
Hands
Hour and minute and small second in black steel
4-minute and power-reserve in polished gold
Strap and clasp
Hand-sewn black alligator
Platinum 950 folding clasp, hand-engraved with the Greubel Forsey logo
