Resonance is omnipresent and therefore more important in defining how things function than is often recognized. It is probably no surprise that resonance has been a widely researched, yet mysterious aspect of timekeeping since Dutch inventor and mathematical genius Christiaan Huygens made his groundbreaking revelations on the topic in the 17th century. In modern watchmaking, Armin Strom has been among the handful of independent watchmakers to further study this phenomenon and incorporate it into some of its watches. Introduced in 2021, the Armin Strom Resonance Zeitgeist celebrated five years of resonance-based Armin Strom watches.
The principle behind resonance is that two oscillating bodies in close-enough proximity will influence each other and eventually synchronize. We have known this since 1665, thanks to Huygens, and the fact that 360 years later, engineers continue to pursue the possibilities in resonance speaks volumes of its powerful potential. If all conditions were perfectly stable, producing an accurate mechanical watch would be a rather more simple task that would still have to tackle the challenges raised by the deterioration of lubricants, the great variations of torque delivery of the mainspring, and a number of other wear, tear, and strain-related issues present in most all spring-driven movements.
Since conditions tend to change rather massively — watches are exposed to shocks and temperature changes on a daily basis during the summer and winter as their wearer shifts between being outdoors and indoors — the challenge of adjusting their movements to provide the best average performance arises. This is why higher-end movements will often say something along the lines of “adjusted to heat, cold, isochronism, five positions.”
Armin Strom’s “patented, time-tested, and scientifically proven” Resonance Clutch Spring, invented by Claude Greisler, is crafted from a single piece of steel and transfers energy between the two escapements to bring them into resonance and average out their errors for maximum accuracy. According to the brand, this “newest generation of resonance is the quickest and most reliable on the market, synchronizing faster than any other watch using resonance.” The Armin Strom Resonance Zeitgeist highlights this brand-defining feature like no other before it by removing as much of the mainplate as possible, making the wavy steel clutch appear to be floating mid-air between the front and rear sapphire crystals.
The two escapements are connected at the hairspring studs on one end and by the clutch that is secured to the balance bridge on the other. As one hairspring winds and unwinds, it transmits a small amount of energy to the other through the steel clutch — this is how the two affect the vibration of each other to achieve a more stable rate. The clutch has its own shock resistance system in the center and, thanks to its shape and thickness, it helps dissolve the effect of shocks, too. Armin Strom claims that its “newest generation of resonance is the quickest and most reliable on the market, synchronizing faster than any other watch using resonance.” Now, this is arguably a small market — but the reason for that lies in the immense difficulty of creating a resonance-based watch movement from scratch.
The two escapements have their respective seconds displays that can be reset by the pusher at the 2 o’clock position. The ARF21 ZG movement comprises 260 components, 39 jewels, has two escapements, each operating at 3.5Hz (25,200vph), and an extended power reserve of 80 hours, thanks to its two mainspring barrels. The hours and minutes are displayed by two filigree hands — potentially to reduce their weight and hence their strain on the movement — while the dial frames are in 18k white gold with polished white lacquer filling. The matte-beige plates of the movement are in sandblasted German silver (or maillechort in French), which is a rather rare and exclusive material in watchmaking mainly due to the fact that is very sensitive to humidity and is difficult to work with.
In line with all that delicate exclusivity, the case of the unique Armin Strom Resonance Zeitgeist watch is in 950 platinum and measures 43mm-wide and 11.55mm-thick. It’s rated water resistant to 50 meters, but neither the black alligator leather nor the sophisticated resonance system call for active wear.
Painstakingly developed and refined by some of the finest engineers and watchmakers over the course of centuries, resonance-based watches remain horological exotica that attracts a certain type of blue-blooded, chronometry-minded collector — of which there are, thankfully, plenty to keep this niche-of-a-niche segment alive. The Armin Strom Resonance Zeitgeist is a unique watch that was priced at $170,000 and has, of course, been sold. You can learn more about Armin Strom’s approach to resonance in watchmaking at the brand’s website.