Hands-On: The A. Lange & Söhne Lange 1 Perpetual Tourbillon Lumen

Aside from its decoration, the caliber L225.1 is equally (if not more) impressive mechanically. If you owned this watch, you’d probably want to stay up past midnight every single day, since that’s when the instantaneous jump of all of the calendar indications occurs. So at the end of each month, an impressive amount of torque is required to advance everything from the month ring to the retrograde day-of-week indicator to the oversized date. What I’m most impressed by is the oversized date advancing instantaneously, even in February, from the 28th to the first. The 3 Hz tourbillon is also a hacking one, to add to the list of features here. Lange’s not the only one doing hacking tourbillons these days, but they were the first, so it’s good to see it on this model. 

While the overall design of the L225.1 is based on the L082.1 caliber found in the classic Lange 1 Perpetual Tourbillon models, there’s quite a bit that’s changed underneath the hood, thanks to the new day/night integration in the moonphase, the white gold rotor, and the unique tourbillon and intermediate-wheel cock design. A closer look reveals a reconfigured positioning of the gear train. Add in modifications required for the “Lumen” execution, like the additional lume plots and sapphire dial construction, and the parts count jumps to 685, up from 624 for the standard ones.