Jaeger-LeCoultre "Reverso Grand Complication Triptych"
Jaeger-LeCoultre remains a leader in complicated watches. The reason the company has been able to create such watches is because it has specialized in producing thin movements. Jaeger-LeCoultre excelled in space-saving mechanisms, and by honing this know-how, it has succeeded in incorporating various functions into complicated watches since the 1990s. Moreover, these functions are highly reliable.
This is the Reverso's 75th anniversary model. This ultra-complex watch boasts 18 functions across three faces. Its escapement is an elliptical equal-length escapement, an improved version of the detent system. In addition to extremely precise celestial and constellation displays, it also features an equation of time display and an extremely easy-to-operate perpetual calendar. To commemorate the release of this watch, Jaeger-LeCoultre has even created a dedicated book. Manual-winding (Cal. 175). 79 jewels. 21,600 vph. Power reserve of approximately 48 hours. 18KWG (55mm x 37.72mm, 17.9mm thick). Water resistant to 30m. Limited to 30 pieces. List price as of the end of August 2019: 339,000 euros.
One of the most outstanding models is undoubtedly the Reverso Grande Complication Triptych, released in 2009. Taking advantage of the Reverso's unique ability to flip the case, this model displays 18 functions on three dials (the front dial, the movement, and the case carrier that supports the case).
The dial features hour and minute hands, a 24-hour display, and a tourbillon. However, rather than a conventional tourbillon, the watch uses an elliptical equal-length escapement, an improved version of a detent. This escapement is extremely efficient, providing a power reserve of approximately 48 hours and a balance wheel moment of inertia of 11.5 mg/cm2. Furthermore, since it requires no lubrication, accuracy remains stable over the long term. In theory, it was an excellent escapement, but due to its cost, it was only used in this watch. It is difficult to combine a complicated watch with high accuracy, but this watch is a rare example of achieving both. If you're a watch lover, this escapement alone is worth buying.
The back of the watch features an astrological calendar with a sky display plate, an equation of time display, and a display showing the movement of the sun. To accurately display the sidereal day, the rotation of the celestial and astrological discs is extremely controlled, with one rotation taking 23 hours, 56 minutes, and 4 seconds instead of 24 hours. Additionally, the tropical year and the equation of time display, showing sunrise and sunset, allow for accurate readings of the astronomical displays.
What's even more interesting about this model is the perpetual calendar located on the case back. It is powered by a movement housed in the case. At midnight, a built-in lever moves, engaging an actuator inside the case carrier and instantly switching all calendars. Because the switch is instantaneous, there is little torque loss, and in theory, it boasts extremely stable accuracy. However, a little care is required. To obtain the correct display, the case must be placed in the carrier at midnight. Otherwise, the lever and perpetual calendar will not engage. However, since the date change can be adjusted manually, it is not a problem even if the lever is disengaged. Furthermore, because the power does not engage at any time other than midnight, no adjustment will damage the movement.
The Reverso Grande Complication Triptych is a masterpiece that utilizes the Reverso's unique features to embed 18 functions across three sides. Normally, such an ambitious watch would fall flat in some way. However, this is not the case for Jaeger-LeCoultre. Its combination of high precision, precise astronomical display, and user-friendly perpetual calendar makes it the pinnacle of complicated watches made by the company.
