Audemars Piguet has significantly upgraded its 38mm Royal Oak Chronograph series, introducing a new in-house movement, the Caliber 6401. This development marks a long-awaited transition from the previously used Frédéric Piguet 1185 movement, which, despite its reliability, had been in service since 1988 and powered the Royal Oak Chronograph since 1997. The new proprietary caliber brings modern enhancements, including a longer power reserve and a more robust chronograph mechanism, while maintaining the watch's elegant dimensions. The collection now features steel and pink gold models, with a slight price adjustment reflecting the upgrade.

This move is particularly notable for collectors with smaller wrists, as it ensures that the 38mm Royal Oak Chronograph now aligns with the brand's larger in-house chronograph offerings, which received their own proprietary movements in 2022. The introduction of the Caliber 6401 underscores Audemars Piguet's commitment to vertical integration and innovation, delivering a refined and contemporary timekeeping experience. Despite not including a flyback function to preserve its slim profile, the new movement offers a patented clutch system that improves durability and pusher tactility, further solidifying the Royal Oak Chronograph's position in the luxury sports watch segment.

Introducing the New Caliber 6401

Audemars Piguet has finally equipped its 38mm Royal Oak Chronograph with a new in-house movement, the Caliber 6401. This marks a significant departure from the long-standing Frédéric Piguet 1185, which has been a reliable, ultra-thin chronograph movement since 1988. The 38mm Royal Oak Chronograph, introduced in 2019, had continued to utilize the Caliber 2385 (AP's branding for the Frédéric Piguet 1185), even after the 41mm Royal Oak Chronograph received its in-house Caliber 4401 in 2022. This update addresses a persistent desire among enthusiasts for a proprietary movement in the more compact Royal Oak Chronograph. The new Caliber 6401 is specifically designed to fit the smaller dimensions, providing a fully integrated chronograph architecture that aligns with modern horological standards.

The in-house Caliber 6401 is a newly developed, compact chronograph movement engineered to power the refreshed 38mm Royal Oak Chronograph. This caliber boasts a comprehensive integrated architecture, featuring a vertical clutch, a column wheel, and a date mechanism that jumps instantaneously at midnight. A notable improvement is the extended power reserve, now 55 hours, a substantial increase from the previous 40 hours. The movement also operates at a higher frequency of 28,800 VpH. Audemars Piguet highlights a patented clutch mechanism within the Caliber 6401, which features a simplified design with fewer components, enhancing robustness and improving the tactile feedback of the pushers. While it foregoes the flyback functionality found in the brand's larger chronograph caliber, this intentional design choice allows the new 38mm Royal Oak Chronograph to maintain its slender 11.1mm thickness, preserving the watch's elegant proportions.

Design Updates and Market Impact

With the introduction of the new Caliber 6401, three distinct models have been launched. The collection includes a steel version featuring the iconic blue grand tapisserie dial, and two pink gold variants. One pink gold model showcases a grey dial with contrasting silver subdials, while the other boasts a sand-gold-toned dial paired with beige subdials and an elegant diamond-set bezel. A key design change accompanying the new movement is the repositioning of the minutes and hours counters on the dial; the minutes subdial is now at 9 o'clock, and the hours subdial is at 3 o'clock. Furthermore, the date window, although still situated between the four and five o'clock markers, is more precisely centered than in previous designs. Significantly, the updated caliber allows for a sapphire caseback, offering a view of the movement's intricate column wheel, a feature absent in the solid casebacks of its predecessors.

The pricing for these new models reflects their enhanced internal mechanism and luxurious finishes. The steel Royal Oak Chronograph (reference 26450ST.OO.1356ST.01) is available at $43,000. The pink gold version (reference 26450OR.OO.1356OR.01) is priced at $84,500, while the pink gold model adorned with a diamond bezel (reference 26450OR.ZZ.1356OR.01) comes in at $91,600. This pricing structure represents a modest increase from the outgoing model's $41,500, which is considered justifiable given the substantial upgrade to an in-house movement. This strategic enhancement is expected to be well-received by collectors who have long awaited a proprietary caliber in the smaller Royal Oak Chronograph. The brand's decision to prioritize a slim profile over flyback functionality in this smaller movement suggests a commitment to maintaining the Royal Oak's characteristic elegance while still delivering cutting-edge horological advancements.