The Roger Dubuis Excalibur Biretrograde Perpetual Calendar: Where Mechanical Poetry Meets Precision
Roger Dubuis has long been recognized for its bold, angular designs and complex open-worked movements. However, the Maison is currently revisiting its roots, blending high-complication watchmaking with a philosophy centered on legibility. The Excalibur Biretrograde Perpetual Calendar stands as a testament to this vision, condensing the demanding traditions of Geneva watchmaking into a sophisticated 40mm pink gold timepiece.
The Biretrograde Philosophy: Form Following Function
At the core of this timepiece is the “biretrograde” display, a signature element that reflects the founder’s obsession with making complex information easy to read. In a standard retrograde mechanism, a hand moves along a semi-circular scale and snaps back to zero upon completing its cycle. The biretrograde system evolves this by using two such displays—often referred to by the Maison as “ecliptic counters”—to indicate the day and date.
This mechanical choice transforms the act of reading the calendar into something “deliberate and alive,” as the hands sweep elegantly across their respective arcs before returning to their origin.
Technical Specifications and Craftsmanship
The Excalibur Biretrograde Perpetual Calendar is not just a feat of engineering but a showcase of luxury materials and artistic layering.
The Movement: Calibre RD850
The watch is powered by the Calibre RD850, a fresh-generation biretrograde perpetual calendar movement developed entirely in-house. This mechanism automatically accounts for months with 28, 30, and 31 days, eliminating the need for manual correction.
Case and Dial Aesthetics
- Case: Crafted from 18K pink gold (750/1000) with a diameter of 40mm and an open case back.
- Dial Construction: A multi-layered, three-dimensional design featuring varnished mother-of-pearl and pink gold accents.
- Celestial Detail: The dial includes an astronomical moon phase disc made of blue aventurine with engraved pink gold moons. This moon phase is remarkably precise, accurate to within one day over 122 years.
- Finishing: The dial utilizes a flange with PVD and satin finishes to enhance depth and contrast.
Strap and Hardware
The timepiece features a pink gold 750/1000 triple folding buckle. For added versatility, it utilizes the Quick Release System (QRS), allowing the wearer to interchange straps easily.
Key Takeaways: Excalibur Biretrograde Perpetual Calendar
| Feature | Specification |
|---|---|
| Case Material | 18K Pink Gold |
| Diameter | 40mm |
| Movement | In-house Calibre RD850 |
| Primary Complication | Biretrograde Perpetual Calendar |
| Moon Phase Accuracy | 1 day over 122 years |
| Dial Materials | Mother-of-pearl, Blue Aventurine, Pink Gold |
A Return to Heritage
The release of the Biretrograde Perpetual Calendar is part of a broader trend for Roger Dubuis to embrace “classic designs.” While the brand is famous for the angular Excalibur series, it is returning to the restrained proportions and classic movements that defined its early years, such as the Hommage and Sympathie series. By pairing the founder’s favorite biretrograde display with modern aesthetics, the Maison bridges the gap between its 1990s origins and contemporary haute horlogerie.
Frequently Asked Questions
What is a biretrograde display?
A biretrograde display uses two hands that travel along arched scales (semi-circles) and “snap back” to the start of the scale once they reach the end. In this specific model, it is used to display the day and date.
How accurate is the moon phase in the Excalibur Biretrograde?
The astronomical moon phase is highly precise, maintaining accuracy within one day over a period of 122 years.
Does the perpetual calendar require manual adjustment?
No. The perpetual calendar automatically accounts for the different lengths of months (28, 30, and 31 days) without requiring manual correction.
Looking Forward
As Roger Dubuis continues to evolve, the integration of the RD850 calibre suggests a future where the brand balances its reputation for “bold” engineering with a renewed commitment to the classical elegance of Geneva watchmaking. The Excalibur Biretrograde Perpetual Calendar serves as a blueprint for this balance—combining extreme technical precision with a legible, artistic presentation.