Ulysse Nardin’s most riveting release from 2020 was the Blast, introduced at last summer’s Geneva Watch Days, which married a skeletonized self-winding tourbillon caliber with an avant-garde, stealth-aircraft-inspired case configuration. At Watches & Wonders this week, the Le Locle-based brand took the Blast to its next — and thus far highest — level of high-horology complication, with the launch of the Blast Hourstriker, a new and innovative take on the classical chiming watch.
The Hourstriker incorporates the groundbreaking technology that UN developed in cooperation with the French audio technology firm Devialet (and debuted in 2019s Classico Hourstriker Phantom) and adapts it to the Blast’s unconventional architecture. The striking mechanism itself is, in fact, unconventional as compared to the traditional type, in which hammers strike a wire gong wrapped around the movement to send sound waves emanating outward, which are then largely muffled by the watch’s exterior materials. In creating Caliber UN-621 — its first in-house, self-winding striking movement, which powers this new timepiece — Ulysse Nardin set out to both improve the sound-quality-to-output ration and make the chiming mechanism visible on the dial side. The movement hosts a flying tourbillon, a variable-inertia balance wheel, and a hairspring, anchor and escape wheel all made of friction-resistant silicon. Sleeker than previous UN Calibers, it uses the “X” motif of recent UN movements, including those in the first-generation Blast models, as part of its design.
From a utility standpoint, here’s how the striker is activated: Press the button at 10 o’clock to trigger the dedicated barrel that drives the mechanism. This action causes the hour rack and inertia regulator to turn and the hammers — visible through the openworked dial at 12 o’clock — to hit the gong, which is specially shaped to bypass the tourbillon cage. Amplifying the chimes, and setting this watch apart from other strikers, is a fine titanium membrane, connected to the heel of the gong by a torsion lever. Just 3/10 of a mm thick, treated with black DLC, and pressed against a grid to prevent deformation, this sensitive membrane basically acts like a hi-fi speaker, moving a large volume of air when struck and thus amplifying the sound waves through the signature “double X” apertures in the rose-gold caseback.
Materially, the 45-mm case of the Blast Hourstriker was designed for optimum acoustics, combining black DLC-coated titanium with 5N 18k rose gold. At 8 o’clock on the case middle is an “On/Off” button, which works with a function-selector hand to silence the timepiece on demand; when it’s “On,” the chimes will audibly indicate the time on the hour and half hour. And despite its complexity, the 330-part movement stores an impressive power reserve of 60 hours.
Like previous Blast models, the Hourstriker’s sharply angled case is modeled on the wing profiles of stealth fighter jets; in profile, it has an aerodynamic look, particularly in the silhouettes of the triple lugs that integrate the case into the strap. Also in keeping with the originals, this new watch comes with three strap options for three distinct looks: rubber, alligator leather, and black high-tech waterproof velvet. The Blast Hourstriker is priced at $104,000, and Ulysse Nardin has not announced a limitation on it, though it will surely be among the brand’s most rare and exclusive timepieces going forward.