A. Lange & Söhne MINUTE REPEATER PERPETUAL Is Rare And Ambitious

A. Lange & Söhne have incorporated two of the most sophisticated horological complications in the latest MINUTE REPEATER PERPETUAL.

With the MINUTE REPEATER PERPETUAL, A. Lange & Söhne once again launches a watch with a minute repeater, this time pairing it with a perpetual calendar. Each one of these complications alone represents a technical feat in itself, the combination of the two, however, poses an even greater challenge. This holds true for the engineers as well as the watchmakers, since the precise tuning and harmonising of all the mechanisms requires a superior degree of technical expertise and craftsmanship.

When the slide integrated into the left-hand case flank is actuated, the chiming mechanism strikes the hours, sounding at a low pitch, the quarter hours with a double tone, and the minutes that have elapsed since the last quarter hour with a higher-pitched tone. The impressive duet delivered by two differently tuned gongs comprises a repertoire of 720 different sequences – one for every minute in the twelve-hour cycle. The sapphire-crystal caseback reveals the orchestrated movements of the gong hammers and the gongs, resulting in their melodious sound. An ingenious system of precisely choreographed racks, snails, levers, and wheels controls the 194-part mechanism.

Just like all Lange watches with a striking mechanism, the MINUTE REPEATER PERPETUAL is designed to superb acoustic quality standards and has a unique timbre. A lucid, clear, and reverberant sound is assured by the hand-tuned gongs that harmonise perfectly with the acoustic characteristics of platinum, the case material. The completion of a minute repeater is highly elaborate; it also calls for acute hearing and extreme dexterity. All components are carefully harmonised with one another by a Lange master watchmaker. This requires adapting, multiple disassemblies, reworking, reassembly and finally testing. As far as the hammers are concerned, the key issues are material, shape, size, weight, and hardness – and above all, just like with a piano, strike.

“Thanks to the development of a new movement, we were able to work towards a perfect sound experience, right from the start ‒ just like with our other models featuring a striking mechanism: the ZEITWERK MINUTE REPEATER, the RICHARD LANGE MINUTE REPEATER or the GRAND COMPLICATION. Combined with the acoustic properties of platinum, we succeeded in achieving a singular sonority and intensity of sound.”
Anthony de Haas, Director of Product Development, A. Lange & Söhne

While the minute repeater chimes the time in the here and now, the technical virtuosity of the perpetual calendar will persist into the distant future. Across decades, the mechanism will assure the precise display of the date, day of the week and month, even taking into account the leap years. The calendar indications must only be corrected by one day but not until 1 March 2100; according to the rules of the Gregorian calendar, the leap year will then be skipped.

This also applies to the moon-phase display that so closely emulates the duration of the synodic orbit of the earth’s satellite that it would take 122.6 years for the display to be corrected by one day. The mechanism is highly sophisticated yet excels with its ease of operation: in typical Lange manner, all calendar indications can jointly be advanced with one single corrector.

The technical sophistication of this multiple-complication watch is reflected in the high-quality artisanship of the four-part dial. Made of white gold and filled with black enamel, it is crafted in the A. Lange & Söhne manufacture in a time-consuming procedure. The immaculate, glossy black surface offers the displays and the characteristic Lange outsize date an elegant stage, providing a contrasting backdrop, thus assuring excellent legibility. The subsidiary dial at 9 o’clock accommodates the day-of-week and the 24-hour displays while a second one located at 3 o’clock is graced by the month and leap-year indications. A third subsidiary dial at 6 o’clock showcases the small seconds and the moon-phase display: both moons in 750 gold are surrounded by more than 100 hand-engraved stars.

The sapphire-crystal caseback provides fascinating insights into the technical complexity and the high degree of artisanal finishing of the newly developed Lange manufacture calibre L122.2. Whether clearly visible or concealed, all 640 parts of the manually wound movement address all expectations that are associated with A. Lange & Söhne’s craftsmanship. The aesthetic highlights include the balance cock that is engraved with a free-hand technique, with the whiplash spring mounted on top. The lateral setscrew assures the precision regulation of the interaction between the escapement and the oscillation system. The three-quarter plate made of untreated German silver is decorated with black-rhodiumed engravings. Four screwed gold chatons adorn its grained surface.

The Lange manufacture calibre is equipped with a screw balance and a freely oscillating balance spring crafted in-house. Decorated with solarisation, the mainspring barrel delivers a maximum power reserve of 72 hours.

With a case diameter of 40.5 millimetres and a height of 12.1 millimetres, the platinum MINUTE REPEATER PERPETUAL is worn on a black, hand-stitched alligator leather strap with a deployant platinum buckle. Limited to 50 watches, the edition is exclusively available at select A. Lange & Söhne boutiques.

Technical Specifications:

MINUTE REPEATER PERPETUAL Ref. 607.091FE
Movement	Lange manufacture calibre L122.2, manually wound, crafted to the most exacting Lange quality standards, decorated and assembled by hand; precision-adjusted in five positions; three-quarter plate made of untreated German silver; balance cock engraved by hand
No. of movement parts	640
No. of jewels	54
No. of screwed gold chatons	4
Escapement	Lever escapement
Oscillation system	Shock-resistant screw balance; superior-quality balance spring manufactured in-house, frequency 21,600 semi-oscillations per hour, precision beat adjustment system with lateral setscrew and whiplash spring
Power reserve	72 hours when fully wound
Functions	Time indicated in hours and minutes, subsidiary seconds with stop seconds; striking mechanism with minute repeater; perpetual calendar with displays for outsize date, day of week, 24-hour display, month and leap year; moon-phase display
Operating elements	Crown for winding the watch and setting the time; slide for activating the minute repeater; corrector for jointly advancing all calendar indications, one corrector each for the day of week, month/leap-year and moon phase
Case dimensions	Diameter: 40.5 millimetres; height: 12.1 millimetres
Movement dimensions	Diameter: 30.0 millimetres; height: 7.6 millimetres
Crystal and transparent caseback	Sapphire crystal (Mohs hardness 9)
Case	950 platinum
Water resistance	Up to 2 bar (20 metres)
Dial	750 gold, black enamelled
Hands	750 gold
Appliques	750 gold, rhodiumed, Roman
Strap	Hand-stitched alligator leather, black
Buckle	Deployant buckle in 950 platinum
Limited edition	50 watches, edition number engraving