The Amazing A. Lange & Sohne Double Split

When I saw that the Double Split was a chronograph I knew it was going to be special. Double rattrapante special? Maybe not. A. Lange & Sohne has successfully come out of left field and produced a chronograph so magnificent that I don’t think anyone was really expecting it. The A. Lange & Sohne Double Split is ingenuity and haute horlogerie all rolled into a lean, mean timing machine.

Before we get too far into this watch, I’ll have to explain a rattrapante or double chronograph. Then explain why the Double Split is perhaps the most advanced mechanical chronograph in the world. Rattrapantes aren’t new to the watch scene but they are rare to find – rarer than even tourbillons. Why? Rattrapante complications are really difficult to manufacture and not everyone knows about them, so the market is also pretty small.

In any case, the following is a brief description of how they work. Most of us are familiar with chronographs, however a rattrapante adds an additional chrono seconds central hand, which continues to run for sixty seconds after the first chrono seconds hand has been stopped so that the time can be observed. This is done by yet another push piece at the 10 position. This function allows for intermediate times to be recorded without completely stopping the chronograph. This is really good but it does have its limitations because this only works for very short timing sessions i.e. anything under 60 seconds. The A. Lange & Sohne double Split improves on this by adding another hand to the chrono minutes counter, thus extending the functionality of the rattrapante to 30 minutes. On top of that, all of the chronograph elements feature a flyback function, eliminating the need to stop and reset.

The case of this timepiece is made exclusively in platinum with a diameter of 43mm. The watch is fitted with a black alligator leather strap, fastened with a platinum pin buckle. Though very functional, the solid silver black dial is surprisingly easy to read. The hour and minute hands are rhodium toned as are the applied Roman numeral hour markers. The regular central chronograph seconds hand is also rhodium toned, while the indicator in the chrono minutes counter is in blued steel. Also in blued steel is the small seconds indicator located in a counter at the 8:30 position. Both of the rattrapante hands are distinguished by their yellow gold color. On the flange is a graduated tachometric scale, which when used with the chronograph can calculate average speeds over a set distance. Just under the 12 position is retrograde power reserve indicator. Protecting all of these dial elements is a scratch resistant sapphire crystal.

The movement Caliber L001.1 is manual wound and is comprised of 465 parts, of which 40 of them are jewels. The movement is almost completely assembled and decorated by hand. The L001.1 uses untreated German silver for its bridges and plates. This revolutionary timepiece features an autonomy of 38 hours when fully wound. The balance spring, which beats at 21,600 VpH in this model was developed specially by A. Lange & Sohne in its state-of-the-art workshop that was opened in 2003. The decorated movement is visible through the exhibition case back made from sapphire crystal.