The Zeitwerk family of watches is one of Lange’s most recognizable, even if it’s not quite as iconic for Lange as the Lange 1. Two chiming versions have been produced: the Zeitwerk Striking Time, which chimes on the hour and on the quarter hours, and the Zeitwerk Minute Repeater. The latter is a so-called decimal repeater; rather than chiming the hours, quarter hours, and minutes past the quarter hour, it chimes the hours, number of ten minute intervals past the hour, and number of minutes past the last 10 minute interval. Now we’ve got a third chiming Zeitwerk: the Decimal Strike, which chimes on the hour, and also at every ten minute interval.
The Zeitwerk Decimal Strike, like the Striking Time, strikes “in passing,” which means that if you have striking enabled (as with the Striking Time, you can turn the strike function on or off at will) it will strike automatically as the hands pass each hour or 10 minute interval. (In French this is called striking en passant; I have no idea what it would be in German. Striking im Vorbeigehen?) The Decimal Strike chimes the hours with a lower pitched chime and the 10s with a higher pitched chime.
Decimal striking is an interesting way to connect the dots between chiming and the digital time display. As with the other two striking Zeitwerks, energy management is key; the energy load on the mainspring can vary much more than in a conventional wristwatch, especially at the top of the hour when all three disks jump simultaneously, and the extra load on the mainspring might adversely affect accuracy. To address this, the Decimal Strike has, as do all Zeitwerks, a constant force mechanism (the complication known as a remontoire d’égalité in French).
All three striking Zeitwerks, including the minute repeater, use the mainspring barrel to power the strike train (most minute repeaters have a separate barrel for the strike train but the Zeitwerk minute repeater does not) so the constant force mechanism is genuinely useful in keeping the A. Lange & Söhne Zeitwerk Minute Repeater Watch Replica running correctly.
The anchor shaped bridge carrying the pivots for the constant force mechanism; center, the blued constant force spring (which is wound by the mainspring, and which passes energy to the escape wheel and balance.
The Zeitwerks have always seemed more interactive than many other complicated watches – not in the sense that you actually fiddle with it physically, but in the sense that if you have one on, you find yourself wanting to look at it much more than you’d ordinarily want to look at your watch, just to see the show when the digits switch. The Decimal Strike, like the Striking Time, adds a score to the performance – one engineered specifically to go with jumps of multiple number wheels, unlike the Striking Time.
The power reserve is possible as a result of twin mainspring barrel. Two straight stacked 25mm-diameter barrels contain springs that are 1,850mm long (each is around 10 times the span of a more traditional spring). Inherent to more mainsprings comes the issue which reduction of torque is much more pronounced as the spring calms. My motion experience can’t fully and thoroughly explain all of the mechanisms here, but I’ll take Lange in their word that this constant force escapement system ensures uniform torque for the entire period of the 31-day power reserve.The L034.1 motion is 37.3mm wide and 9.6mm thick, made of 406 parts including 62 jewels. It functions at 21,600vph and has a Nivarox balance spring. When you flip the watch around, you see that the kidney-shaped exhibition that gives you a look at the constant push escapement system, a hand-engraved equilibrium cock, and the conventional 3/4 movement plate. And on the top left you’ll see where the rotation key is inserted in order to finish the watch. So as to easily access this, the deployant clasp allows the strap to fully open on one side.The case is 45.9mm broad and 15.6mm thick, making it a fairly substantial watch so far as wrist presence goes. That having been said, the movement and how much has to enter a watch with a 31-day power book is clear, and it would be naive to expect a little case. Hell, everything else about the piece is so discreet you might also have something about it that grabs attention, right?
The Zeitwerk Decimal Strike is a limited edition of 100 pieces and is priced at €120,000 (approximately $127,700 at time of publishing). Official U.S. Dollar pricing will be announced after SIHH.
For more, visit A. Lange & Söhne online.
The Zeitwerk Decimal Strike: movement, Lange caliber L043.7, hand wound, 36mm x 10.0mm; frequency 18,000 vph; constant force mechanism (remontoire d’égalité) 36 hour power reserve. Decimal strike at the hours and ten minute intervals, im Vorbeigehen, with on/off selector. Case, Lange Honey Gold; 44.2mm x 13.1mm. Limited to 100 pieces world wide; price at launch, €120,000 or about $127,700 at the time of writing. This is the time of year I get to mention I coined the term “decimal repeater” in 2005 (my sole contribution to horological technical nomenclature).