This is the eleventh creation in Jaeger-LeCoultre’s haute horology Hybris Mechanica collection and, at 7.9mm thick, represents the world’s smallest minute repeater/grand complication with an automatic movement. The real feat of this watch is the ratio between the thickness of the movement and the thickness of the case. “People don’t know how we can place a 4.8mm movement inside a 7.9mm case,” says Jaeger-LeCoultre creative and marketing director Stephane Belmont. He says normally the case of a 4.8mm movement would be 9.5 or 10mm thick. “We did it by questioning how the components in a watch are arranged, and then rearranging them.” It started with the rotor. A movement’s oscillating weight is normally placed on the central axis at the back of a movement, but the Hybris Mechanica uses a newly developed front-side peripheral rotor, which circles the circumference of the dial on a system of ceramic ball bearings, thereby reducing the thickness. It can be seen through a row of windows in the dial, running along the inside of the inner bezel. Although it’s the clockwise rotation that winds the caliber, the rotor moves in either direction.
The hammers are another key to the slimness of the watch. The brand’s patented trebuchet hammers were first introduced in 2005, and are hinged, like a catapult – the head of the hammer is on an axis – allowing the strike to be accelerated in a way that requires 80% less energy than traditional gongs. What this allows Jaeger to do is reduce the size of the barrel by more than 50%, without losing power reserve.
Also narrowing the package is the flying tourbillon, which takes less space because of the absence of an upper bridge. In addition, the escapement has a flying balance making it 25% thinner than a traditional tourbillon escapement. Also, “If you look closely at the tourbillon,” says Belmont, “you will see that it is on the same level as the dial. We integrated the tourbillon into the dial in order to save a few 10ths of a millimeter.”
Other impressive details of this watch include a retractable pushbutton to activate the repeater, and a “silent-timelapse” reduction system, which means that unlike conventional repeaters, there is no gap between the chime of hours and the minutes when there are no quarter hours to chime in between.
This is truly a unique watch, and a complete re-imagining of the tourbillon/minute repeater combination. In addition to its innovative engineering, the silver-grained dial is gorgeous, and the strike sounds fantastic – the gongs are attached to the sapphire crystal, which, because it is so hard, magnifies the vibrations and heightens the sound. It is a 75-piece limited edition.