Good Vibrations: Armin Strom Celebrates Five Years Of Resonance Technology With Zeitgeist

Swiss independent brand Armin Strom is in a celebratory mood, for it is five years since the Biel/Bienne-based, family-owned company introduced its resonance technology. And to commemorate the milestone, the watchmaker decided to create something rather special – a stunning, skeletonized, unique resonance timepiece called Zeitgeist.

In watchmaking, the phenomenon of resonance involves two oscillating mechanisms that transmit vibrational energy between one another, so each affects – and corrects – the other’s rate, thus improving accuracy.
 

As the eminent horologists Christiaan Huygens, Abraham-Louis Breguet, and Antide Janvier discovered, when two pendulums or balance wheels are fixed to a common support, small vibrations are shared through the supporting structure. A tiny force is either added to or subtracted from the opposite oscillator by this energy, averaging their rate by speeding up the slower one and slowing down the faster one. That carries on until both synchronize and keep each other at a constant rate.

Armin Strom’s impressive take on resonance entails a butterfly-shaped resonance clutch spring. A flexible suspension made from steel, the patented Resonance Clutch Spring connects both the hairsprings of a pair of oscillators, letting the vibrations pass to the opposite balance wheel.
 

It doesn’t just perform well – it takes a matter of minutes for the 3.5Hz balances oscillating in opposite directions to synch – but it looks fantastic too. The twin regulators set a symmetrical visual tone for the timepiece, into which the brand has channeled its technology.
 

Armin Strom first used its resonance system in Mirrored Force Resonance, with twin small seconds displays, then in its Pure Resonance, with single small seconds. It has even made a Minute Repeater Resonance and a Dual Time Resonance with two independent time displays.

To create its Zeitgeist, Armin Strom has essentially taken its Mirrored Force Resonance design, with twin oscillators and corresponding twin small seconds displays, and given it a contemporary makeover. And at the heart of which is another of the brand’s traditional specialties: skeletonization.
 

Before Founder and CEO Serge Michel and Co-founder and Master Watchmaker Claude Greisler took over the reins of the brand in 2006, Armin Strom was known for its openworked watches, hand-skeletonized by the man who established the brand – and lent his name to it – Mr. Armin Strom.
 

Zeitgeist pays tribute to that tradition of skeletonization, thanks to the paring down of its mainplate, bridges, and dial discs. As a result, this leaves a number of the moving parts of the Calibre ARF21_ZG visible in all their glory. Stealing the show at 9 o’clock are the twin oscillators coupled with the clutch spring, their presence now made all the more spectacular by a large void that has been created by cutting out part of the mainplate beneath them.