It can be so hard to say goodbye to yesterday, but improvements in watch function and efficiency do make it significantly easier. It’s not often that legendary watch brands phase out long-time calibers in favor of something completely new but Audemars Piguet prepared us a year ago when it announced the end of the Caliber 5134, which had its swan song in John Mayer’s Limited Edition Royal Oak.
Now, after 10 years of the Caliber 5134 and 47 years of the Caliber 2120/2800 (on which the 5549 was based), the Swiss luxury firm has now inaugurated the brand-new Caliber 7138 with a handful of new references.
From the 5134 to the 7138
Since the debut of its iconic perpetual calendar watch ref. 5548 in 1978, all of Audemars Piguet’s perpetual calendar models were based on the architecture of its Caliber 2120/2800 movement (which itself is based on the 2120 movement that debuted in 1967). Upon its release, the 2120/2800 was not only the world’s thinnest perpetual calendar but it sparked a significant industry-wide increase in perpetual calendar production.
Incredibly thin just like its predecessors, the 5134 debuted in 2015 with 374 components and at just 4.3mm thick. Powering a plethora of Royal Oak and Code 11.59 models in that time, the movement was pretty fantastic but AP felt like it could still be improved, as they should have.
Likely preparing for phasing out the 5134, AP came out with the Royal Oak RD#2 concept in 2018 (which got a production version in 2019), improving the perpetual calendar by putting the functions on one level to achieve a 2.89mm thinness while also allowing the user to set and correct the complication tool-free.
And then, separately, there was the Royal Oak Jumbo ref. 16202ST, a 50th-anniversary RO model in 2022 that got a new caliber 7121, which brought the 2.75Hz of the 5134 to 4Hz, and also increased the power reserve from 40 hours to 55 hours. This also featured a quick-set date.
So Where Does That Leave Us?
Essentially, the new Caliber 7138 leveraged the improved perpetual calendar thinness of the RD#2 and the small improvements from the 7121 to make an all-around improved movement over the outgoing 5134. Carried over is the 55 hours of power reserve, the single-layer perpetual calendar layout, and the 4.1mm thickness.
A perpetual calendar watch is a very complicated movement. And with the 5134, some of the corrections of the subdials had to be performed by small tools going into the side of the case, which could damage the watch movement. Now, all corrections are made via the crown, which adjusts the dial using four different positions, making it “impossible to desynchronize the watch and damage the mechanism,” which could happen if the user attempted to set the watch between 9PM and 3AM.
The New Watches
The new Caliber 7138 automatic is debuting in the new Royal Oak Perpetual Calendar Selfwinding references 26674ST and 26674SG. Both 41mm across with a 9.5mm thickness, the watches feature the same octagonal bezel with six white gold screws. While the 26674ST sports a stainless steel case with blue dial, the 26674SG features an 18k sand gold case with a matching galvanic dial color — both with the signature Grande Tapisserie dial patterns.
With the improved design and absence of the correctors, the water resistance has increased from a mere 20m to 50m. Also, as expected, the integrated Royal Oak bracelet returns here in the same metal materials as the respective cases. Nothing here has changed, fortunately.
Each watch features the same four subdials on the dial, including the moonphase at the bottom. While little has changed here, the updates have been subtle, including the 1 instead of 52 at the 12 o’clock position. Likewise, Monday has now been placed at the top of the day subdial, while 1 is at the top of the calendar date subdial. The date subdial has also been updated so that the numerals are positioned and sized based on the size of the digits themselves so you can read them easier. And inside the day-of-the-week subdial, a 24-hour indicator has been put in the center.
Also a New Code 11.59
Along with the headlining Royal Oaks, the new Caliber 7138 automatic has been placed in the Code 11.59 Perpetual Calendar ref. 26494BC as well. The Code 11.59 launched in 2019, which is when the Perpetual Calendar variant debuted as well.
Aside from the 18k white gold case that’s been brought down to 41mm across and 10mm in thickness, the new inaugural version for the 7138 features the same dial updates as the new Royal Oaks, and on a textured blue aventurine dial. However, the water resistance has only been improved to 30m this time. It’s affixed to a matching blue rubber-coated strap with calfskin lining.
Spec Sheet
Case Size: 41mm
Case Thickness: 9.5mm (Royal Oak), 10mm (Code 11.59)
Case Material: Stainless steel or 18k sand gold (Royal Oak), 18k white gold (Code 11.59)
Water Resistance: 50m (Royal Oak), 30mm (Code 11.59)
Movement: In-house Caliber 7138 automatic perpetual calendar
Band: Stainless steel or 18k sand gold (Royal Oak), blue rubber-coated strap with calfskin lining (Code 11.59)
Limited Edition?: No
Pricing & Availability
Not limited to edition size, these inaugural Caliber 7138 perpetual calendar watches in both Royal Oak and Code 11.59 formats range from $109,300 to CHF 130,000 (~$144,800). Head over to Audemars Piguet’s website to learn more.
Recap
Audemars Piguet Caliber 7138 Perpetual Calendar Caliber Watches
Replacing the long-standing Caliber 5134, Audemars Piguet debuts the new Caliber 7138 perpetual calendar, which is thinner and more efficient. It’s put in new Royal Oak and Code 11.59 models.
