The characteristic that has defined Audemars Piguet’s Concept watches, the integration of case and movement, is also on display in this new model. The movement, hand-wound Calibre 2930, features a twin barrel that provides a 10-day power reserve, providing energy for the tourbillon and second time-zone (GMT) display. The escapement, which beats at a frequency of 21,600 vph (3 Hz), rotates inside the tourbillon carriage every 60 seconds. The tourbillon cage is made up of 85 components, yet weighs only .45 grams. Each cage requires three days to assemble, including two full days to install, and the entire mechanism represents more than two full weeks of work. Each component is beveled, polished, assembled and balanced by hand. Audemars Piguet’s proprietary parallel double barrel system generates a constant force during some 237 hours of autonomy, enhancing timekeeping precision.
The GMT display at the 3 o’clock position, which shows the time in a second time zone, is adjusted using the push-piece at 4 o’clock: each push advances the time by one hour. This indicator, based on 12 hours, combines two superimposed disks. The first, on which the figures are inscribed, completes one turn every 12 hours. The second, just below it, completes one turn every 24 hours and is divided into two colored halves that indicate whether it is daytime (white) or nighttime (black).
The energy from Caliber 2930’s two 10-day barrels is fed into the gear train at the same time by means of a single pinion bridging the two. Audemars Piguet says that this is a gentler means of transmitting energy than the more common system of two series-linked five-day barrels. It also reduces pressure in the gearing, with the friction in the barrels offsetting torque variations, and gives increased running precision, greater power reserve and enhanced reliability, according to AP.
The Royal Oak Concept GMT Tourbillon also features a selection-indicator mechanism. According to the position of the winding stem, the hand positioned on the dial at 6 o’clock indicates its selected function. The “H,” “N,” and “R” indications correspond to the three positions, standing for time-setting, neutral, and winding, respectively.
The watch is on a white rubber strap, which matches the white ceramic bezel, push-pieces and crown and is integrated into the distinctive octagonal case.