Introduced at SIHH 2017 by A. Lange & Söhne, the ZEITWERK DECIMAL STRIKE makes time audible in a new way: its striking mechanism sounds every ten minutes. The case of this timepiece, limited to an edition of 100, consists of honey gold as used exclusively by Lange.
Introduced in 2009, the A. Lange & Söhne ZEITWERK gave time a new face with a mechanical jumping numerals display. Now, the ZEITWERK DECIMAL STRIKE is enriching the successful, unusually designed watch family with a third model featuring an acoustic time indication.
Given its mechanical architecture, the ZEITWERK calibre offers ideal prerequisites for the integration of a striking mechanism: A large amount of energy is built up for advancing its mechanical, precisely jumping numerals displays. As was already the case with the ZEITWERK MINUTE REPEATER and the ZEITWERK STRIKING TIME, this energy can be put to good use by an automatic striking mechanism.
In the new model, it relies on two differently tuned gongs to indicate the full hours as well as the ten-minute intervals between the start of one hour and the next. The two hammers that are visible on the dial side consist of polished steel and, like the hammer bridge, are decorated with a tremblage engraving. The hammer on the left strikes the low-pitched gong once every full hour. The right-hand hammer sounds a higher-pitched tone every ten minutes, or in other words, every time a new ten-minute interval begins.
With its large, precisely jumping numerals display, the ZEITWERK DECIMAL STRIKE assures excellent legibility. In one-minute intervals, the units disc instantly advances by exactly one increment. The patented constant-force escapement between the mainspring barrel and the balance delivers the power. It makes sure that the balance has a constant amount of energy across the entire power reserve period. The high-pitched tone sounds every time the tens disc advances; at the start of the hour, when the low-pitched tone is struck, all three numeral discs jump synchronously by one increment.
The striking mechanism can be switched off. When the button at 4 o’clock is pressed, the hammers are deflected away from the gongs. This also happens when the crown is pulled to set the time. The technical concept is paired with an innovative material. The case of the ZEITWERK DECIMAL STRIKE, limited to an edition of 100 watches, consists of honey gold as used exclusively by A. Lange & Söhne; it has a diameter of 44.2 millimetres. The lavishly finished, manually wound calibre L043.7 has a maximum power reserve of 36 hours.
Lange-typical quality hallmarks include the three-quarter plate made of untreated German silver and decorated with Glashütte ribbing, the hand-engraved balance cock, and a campoised balance with a free-sprung hairspring crafted in-house.