Central Impulse Chronometer

Abraham-Louis Breguet tried to solve this problem two hundred years ago. The natural escapement, his attempt at delivering energy directly to the balance wheel without the friction losses of a conventional lever escapement, was theoretically brilliant and practically unreliable. It worked in pocket watches under controlled conditions. It failed in the real world. George Daniels picked up where Breguet left off in the twentieth century and developed the co-axial escapement, which Omega eventually adopted and scaled to industrial production. But Daniels also built something more radical: the Independent Double Wheel Escapement, a mechanism with two separate escape wheels delivering impulse directly to the balance from both sides, alternating with each oscillation. Daniels believed it could not be miniaturized into a wristwatch. Bernhard Lederer proved him wrong.

Lederer is a German watchmaker, now in his mid-sixties, who spent decades working behind the scenes building complex mechanisms for other brands and private collectors. He had personal conversations with George Daniels before Daniels died in 2011. Those conversations informed everything that followed. When Lederer finally stepped into the spotlight with his own name on the dial, he chose the hardest possible problem to solve: build a wristwatch escapement that delivers impulse directly to the balance wheel, from the center of the mechanism, using two independent gear trains, each with its own mainspring barrel, its own escape wheel, and its own constant-force remontoire. The result is the Central Impulse Chronometer.

The Caliber 9012 has 210 parts and 45 jewels in the 44mm version, or 212 parts and 36 jewels in the 39mm. The movement beats at 21,600 vibrations per hour, 3 Hz, with a 38-hour power reserve from two mainspring barrels. But those specifications do not convey what is actually happening inside this watch. There are two completely separate gear trains. Two barrels. Two remontoires that recharge every ten seconds. Two escape wheels made of hardened titanium. The balance wheel receives a regulated burst of energy every five seconds, alternating between the two gear trains. The inspiration is John Harrison's H4 marine chronometer from 1759, the clock that solved the longitude problem. Harrison used a remontoire to deliver constant force. Lederer uses two of them, one per gear train, to deliver constant force from both sides of the balance wheel.

The escapement geometry is set at 120 degrees, wider than Daniels' 100-degree configuration, which reduces the inertia of the impulse and minimizes the disturbance to the balance wheel during each energy delivery. A proprietary component Lederer calls the waiting pallet ensures correct alignment at low amplitude. At higher amplitudes, the escapement operates in pure direct-impulse mode. At lower amplitudes, when the mainspring is approaching depletion, it transitions to a hybrid indirect-impulse mode that maintains stability. The system is self-adjusting. When the remontoire can no longer recharge, the watch stops. Like the Gronefeld 1941 Remontoire, the Central Impulse Chronometer would rather show no time than show inaccurate time. That philosophy appears in every serious constant-force watch and it tells you something about the people who build them.

The dial tells you something is different before you understand what. There are two seconds subdials, and the seconds hands rotate in opposite directions. One clockwise, one counterclockwise. They move in mirror-image synchronization because they are driven by two separate gear trains running in opposite orientations. Two figure-eight cutouts in the dial reveal the escapement and remontoire action in real time. You can watch the mechanism work. The two escape wheels, the two remontoire springs recharging, the balance wheel receiving its alternating impulse. It is hypnotic. Most watch dials are static surfaces that display time. This dial is a window into the machine.

The case is 18-karat white gold in the blue dial configuration, 44mm with two box sapphire crystals, front and back, that allow light to enter the movement from both sides. The 39mm version brought the watch to a more wearable size with a movement measuring 35mm in diameter and 4.95mm thick. Both sizes maintain the same dual-gear-train architecture. The movement finishing is three-dimensional in a way that most haute horlogerie movements are not. Because the caliber has two complete gear trains layered within the same space, the bridges and plates exist on multiple levels. Looking through the caseback is like looking into a mechanical canyon.

The Central Impulse Chronometer won the GPHG Innovation Prize in 2021. The Innovation Prize is the category that recognizes genuine technical advancement, not just beautiful design or skilled finishing, but a new idea that moves watchmaking forward. Lederer earned it because the CIC does something that nobody else has done: it takes an escapement concept that the greatest horologist of the twentieth century said could not work in a wristwatch and makes it work. Not as a prototype. Not as a concept piece. As a production wristwatch that you can wear.

I think about this watch in the context of what Breguet started, what Daniels advanced, and what Lederer finished. Three watchmakers across three centuries, each building on the last. Breguet had the idea. Daniels had the mechanism. Lederer had the engineering to miniaturize it and the constant-force architecture to make it reliable. The Central Impulse Chronometer is not just a watch. It is the conclusion of a 200-year engineering argument about how to deliver energy to a balance wheel. Lederer closed the argument.

The honest critique is the same one that applies to the Gronefeld. Production is tiny. The 44mm white gold blue dial was limited to 25 pieces. Pricing at auction ranges from $70,000 to $140,000 depending on configuration and provenance. You are not walking into a boutique and buying one. This is a watch that exists at the intersection of art and engineering, produced in numbers that ensure most collectors will only ever read about it. But reading about it matters because the technical achievement is real regardless of whether you can own it. The dual-gear-train, dual-remontoire, central-impulse architecture is one of the most sophisticated escapement systems ever built for the wrist. Bernhard Lederer spent decades in the shadows building for others. When he finally built for himself, he built something that Breguet imagined, Daniels attempted, and nobody else has matched.