With 2022 being the 50th anniversary of the Royal Oak, Audemars Piguet has already launched a slew of new models barely a month into the year. While the headline watches are no doubt the Royal Oak “Jumbo” ref. 16202 and its skeletonised sibling, the Audemars Piguet Royal Oak Selfwinding 37 mm ref. 15550 is a more accessible watch, both in terms of price and availability. It too gets an upgrade for the 50th anniversary in the form of a new movement, the cal. 5900, along with a revamped case, dial, and bracelet.
As familiar as it might seem, the ref. 15550 received as complete a makeover as possible while still retaining the trademark design. Individually the changes are minor but together they create a watch that looks and feels better than the previous version of the mid-size Royal Oak.
The tweaks can be spotted even at arm’s length, Audemars Piguet Royal Oak Selfwinding 37 mm including the streamlined dial that has been cleaned up to reduce the text, giving it a look similar to that found on the latest-generation Royal Oak 41 mm ref. 15500.

The newly minimalist dial works especially well with the mid-size case, with the empty space looking just right. In contrast, the dial style seems almost bland on its larger counterpart.
The case and bracelet also get their own nips and tucks, though the alterations are far more subtle. Amongst the changes are slightly wider bevels along the edge of the case, making it seem to taper more towards the lugs, emphasising the dial and bezel. This gives the watch tighter lines and leaves it looking slightly larger.

These changes are accompanied by new colours for the dial, including the currently fashionable dark green and light blue. While the “ice” blue has been found on other models in the past, the dark green dial is novel.

The Audemars Piguet Royal Oak Selfwinding 37 mm new colours create a variety of choice that was absent in the past for the mid-sized Royal Oak (and also the larger models), which is a good thing.
At US$24,100 in steel, the ref. 15550 costs exactly the same as the outgoing ref. 15450 (though the price of the latter was increased by approximately 20% just recently). While that’s substantial, the price remains competitive in relative terms (compared to its rival from Geneva for instance).

And by today’s standards, that is pretty much a bargain not just any high-end sports watch, but the Royal Oak, with all the prestige, history, and quality that entails
Having gotten rid of most of the text on the dial, the focal point now turns to what remains, which is the applied logo under 12 o’clock. That has been upgraded from a mere printed logo to a solid-gold appliqué produced in a high-tech manner: thin layers of 24k gold are chemically deposited repeatedly to build up a three-dimensional structure in a process known as galvanic growth.
Like the dial, the case has been reduced to the essentials. While it retains the same 37 mm diameter as the earlier generation, it has been slimmed down from 9.8 mm to 9 mm.

The improvements to the design don’t stop at the case, but continue on to the bracelet. The pronounced taper of the lugs in turn result in a more tapered bracelet, making it slightly more elegant and definitely lighter in weight. The weight reduction will improve wearability, especially for the solid-gold model.
The thinner case is largely thanks to the cal. 5900, a movement that includes a full balance bridge that supports the free-sprung balance, just like in its predecessor. Like the cal. 5800 found in the Royal Oak 34 mm, the cal. 5900 is most probably produced by specialist, as opposed to being an in-house calibre.

Like Audemars Piguet’s own movements, the cal. 5900 bears features typical of a modern, high-quality movement designed to be produced in large numbers. As a result, it exhibits a neat, thorough decoration that is largely mechanically applied, instead of the artisanal finish found in the brand’s top-end watches (that have six figure price tags).