While the attention was mainly focused on the new CODE 11.59 collection at the SIHH 2019, Audemars Piguet had multiple other new watches to show in its Royal Oak range – including a superb Salmon dial Jumbo Royal Oak and one extremely important watch, a new Audemars Piguet Royal Oak Selfwinding 41mm. Meet the reference 15500ST, replacing the 15400 and introducing several massive updates, including a newly positioned date and, mainly, a brand new movement.
The Audemars Piguet Royal Oak Selfwinding 41mm reference 15400, a watch introduced in 2012, is now out of the collection… But don’t be sad, there’s a new model to replace it, and it corrects some of the flaws found on the older model.

The Audemars Piguet Royal Oak Selfwinding 41mm reference 15400 was launched in 2012 as an update of the reference 15300, the 39mm, automatic version of the Royal Oak – a watch that was a sort of sportier, more robust, more accessible, less hardcore version of the Royal Oak Jumbo Ultra-Thin, with a more classical automatic movement, a slightly thicker case and overall, a more mainstream take on the Royal Oak design. While the size of the case grew, the movement inside these two references was the same, the calibre 3120 – a movement with a relatively small diameter of 26.60mm.
Because of that, the date on the reference 15400 was positioned far in the middle of the dial, something that Audemars Piguet compensated by adding a small hour marker next to the date window. On a personal level, this has never been an issue for me, but some collectors complained about the fact that the calibre 3120 movement was too small for a 41mm case. Other than that, the calibre 3120 has always been a very good engine – reliable, precise, nicely decorated.

This possible issue of the date window and a caseback with a movement too small for the case is now over, as Audemars Piguet has a new watch in the collection to replace the reference 15400. Fitted with a new movement, a new dial (and not just a new date position) along with several other updates… Let’s take a look at the new Audemars Piguet Royal Oak Selfwinding 41mm 15500.
So Audemars Piguet has a new automatic Royal Oak… But don’t expect drastic changes, the concept is still the same. Compared to the original icon, the Royal Oak “Jumbo” Extra-Thin 39mm reference 15202, the new reference 15500 is still larger, thicker, bolder, more robust and slightly less refined in its execution – but also less expensive and probably easier to find new in boutiques. When compared to the older reference 15400, the new model feels like a simple update, with minor changes. However, if the overall concept and design remain similar, there is more than meets the eye in this new 15500.
The main update is, of course, the new movement. Audemars Piguet introduced an entire line-up of new in-house movements with its CODE 11.59 collection – tourbillon, integrated chronograph and automatic time-and-date – and thus it is natural to see these new calibres being implemented in other collections. The reference 15500 is equipped with the calibre 4302, the same movement as used in the CODE 11.59 Selfwinding (more details here). This movement is entirely new and has been developed internally by Audemars Piguet as a modern calibre. It measures 32mm in diameter, which certainly is more appropriate for modern-sized watches, including this 41mm Royal Oak Selfwinding. Compared to the previous calibre 3120, it displays several mechanical improvements. The frequency of the regulating organ is now 4Hz, compared to 3Hz in the past. The power reserve has been increased to 70 hours over the 60 hours for the former ref. 15400. Having a new and larger movement results in more balance on the caseback side. The movement is now dimensioned according to the diameter of the watch, something that certainly is pleasant. Regarding decoration, the calibre 4302 doesn’t disappoint. It features a skeletonized gold rotor with superb sharp anglages. Bridges are adorned with Geneva stripes, and the bevels are polished. The layout of this calibre 4302 is also quite pleasant, with multiple technical parts being visible.
For the rest, this Audemars Piguet Royal Oak Selfwinding 41mm 15500 retains all the attributes of the collection, meaning a superbly executed case, with brushed surfaces enlightened by polished details, the iconic octagonal bezel with eight white gold screws and its chain-like integrated steel bracelet that participates so much in the design of this watch. As usual, the finishing and assembly are flawless, with sharp adjustments of all the parts and super-clean demarcations lines between the brushed and polished surfaces.