With its open architecture offering superb visual access to the mechanism, the movement of the Double Tourbillon 30° is hand-wound. It has a 120-hour power reserve guaranteed by four fast-rotating coaxial barrels.
In this version, the Double Tourbillon 30° features an asymmetric case. The rotating Double Tourbillon cage system has in turn been repositioned between 7 and 8 o’clock. The Double Tourbillon 30° has been redesigned and notably features a new tourbillon bridge, to be displayed “in reverse”.
This Edition Historique commemorates the closing of the Double Tourbillon 30° Contemporain Vision line after six successful years. The inventors of the now iconic Double Tourbillon 30° explain their reasoning and philosophy in text on the dial and on four hand decorated curved plates screwed onto the caseband.
With a preference for discretion, the Double Tourbillon 30° now appears in a less extrovert and one might almost say ‘secretive’ style, even though such a splendid dial naturally hints at the treasure it is guarding. The timepiece presents an unusual and particularly wide subdial at 6 o’clock with a slender blued steel hand testifying to the four-minute rotation of the outer cage of the Double Tourbillon 30°.
Greubel Forsey's first invention is an innovative Double Tourbillon mechanism, with one Tourbillon cage - inclined at 30° and rotating in 60 seconds - inside another cage, completing a full rotation once every four minutes, to average out gravity-induced errors on the oscillator.