Audemars Piguet Royal Oak, Perpetual Calendar, Yellow Gold

A Perpetual Calendar Royal Oak

The first Royal Oak to feature a perpetual calendar complication was released in 1983, as the reference 5554 (later designated the ref. 25554). Following this, the ref. 25654 was introduced (seen in this example), featuring the same refined aesthetic. As a result of the watch’s divergent approach, only 800 examples of the ref. 25654 were produced between 1983 and 1998 - limited to just 422 in yellow gold.

At the time, the combination of the sporty, Royal Oak case and complicated perpetual calendar movement was an unusual, forward-thinking approach by the brand. In recent years, the Royal Oak Quantième Perpétuel has since been the canvas on which Audemars Piguet have experimented and redefined its perpetual calendars, introducing various unique interpretations. This reference 25654 represents one of the first steps in this ongoing legacy.

The Design

This rare, gold, ref. 25654BA example features a lightly-textured, champagne dial with black indicators and blued subsidiary hands. The layout of the dial includes all the traditional indications of a perpetual calendar: day, date, astronomical moon (with graduation for moon age) and month. It features original gold stick hands, a feature rarely found in Royal Oak watches. The sub-dials are slightly recessed, giving the dial greater depth and texture. It features the "Audemars Piguet" signature in small lettering, only found on the earlier examples of the reference 25654, before the brand adopted its modern signature style. 

The gold case and bracelet are excellently finished, with angular, beveled and polished edges - striking the perfect balance between utilitarian function and elegant design. The polished screws, bezel and case edges fantastically-contrast with the brushed surface of the case and bracelet. The watch features its original unsigned crown, white gold clasp and clasp cover with correct "AP" signature. 

At 39mm in diameter, and only 9.3mm thick, this Royal Oak Quantième Perpétuel case is a beautiful twist of perspectives and size. On the reverse, the outer-case back correctly displays the unique serial number (C-61XXX), along with its sequential case number (6XX). The Ref. 25654ST is housed in a 39mm case (like the 5402 'Jumbo’) - succeeded in 2015 by the latest generation of 41mm perpetual calendars.

The Movement

This Royal Oak Quantième Perpétuel is powered by the AP caliber 2120/2800, derived from Jaeger-LeCoultre’s legendary ultra-thin JLC 920 calibre movement. The caliber 2120 was an initial project of Jaeger LeCoultre in 1967, funded and contributed by Audemars Piguet, and famous for its adoption by Audemars Piguet, Patek Philippe and Vacheron Constantin.

The ultra-thin automatic 2120/2800 calibre features 38 working jewels, Gyromax balance and four ruby wheels to support the full-diameter rotor, which runs on a beryllium rail for stability. The AP calibre 2120 remains the thinnest full-rotor self-winding movement in the world, considered by many as one of the most technically refined wrist-watch movements ever made.

The Set

This Royal Oak 25654BA is accompanied by an Authenticity and Exclusivity Certificate issued by Audemars Piguet, which confirms the case, movement and serial numbers. It is also accompanied by an Extract from the Archives (to follow).

Closer look