How Fast Does A Watch Need To Be?
A watch’s frequency is measured by two different terms: hertz (Hz) and vibrations per hour (VpH) (Don’t worry, they’re interconnected). Hertz refers to the number of oscillations that the balance wheel in a watch’s movement makes in a single second. A half oscillation, meaning a swing of the wheel in either direction, is equal to one vibration. Here’s what that looks like in action: a watch with a frequency of four Hz makes four full oscillations per second, or eight vibrations, which adds up to 28,800 vibrations per hour.
Mechanical watches on the extremely high end of the spectrum run at a frequency of ten Hz or more and measure time down to 1/20th of a second. That’s extraordinary, though - most mechanical watches run at 2.5 to 4 Hz (18,000 to 28,800 vibrations per hour), which is more than enough for accurate, dependable timekeeping. (It’s worth pointing out that quartz watches, in comparison, are orders of magnitude more precise than any mechanical watch - quartz crystal vibrates at 32,768 Hz.)
So why push mechanical movements faster? Better question: Why not? A mechanical watch movement that hits 5 Hz (36,000 vph) or above is usually known as a “high-beat” movement, and can span the showoff spectrum from a clean-and-classic Grand Seiko SBGH205 ($5,800) at 36,000 vph to a six-figure Audemar Piguet Jules Audemars Chronometer with its intensely complex, absolutely beautiful 6 Hz (43,200 vph) movement. Other watches, like the Vacheron Constantin Traditionnelle Twin Beat Perpetual Calendar in the above image, are built to switch between lower and higher frequencies in order to conserve energy when not in use.
When watchmakers break out of the conventional 2.5 to 5 Hz range, it’s generally for bragging rights. For instance, the $40,000 Breguet Classique Chronométrie 7727 runs at 10 Hz - 72,000 vph, if you don’t want to bust out your calculator app - and it’s a feat of engineering that required certain pieces within the movement to be made from lightweight, wear-resistant silicon instead of metal in order to enable that kind of frantic pulsing. Just to show off, the Breguet has a teensy dial on the face, near 1 o’clock, with a hand that makes a full rotation every two seconds. It doesn’t do a damn thing to help the wearer tell time; it’s a flex - the equivalent of a Ferrari with a see-through engine cover, it’s there to remind you of the spectacular engineering underneath.
Since speed is a battleground where the war never ends, just this year Zenith introduced the Defy Inventor, a limited-edition mechanical watch with a movement that hits 18 Hz (129,600 vph) thanks to a wildly radical design that replaces the balance, balance spring, and lever with a single silicon piece dubbed the Zenith Oscillator, among other upgrades and innovations best understood by people with engineering degrees.
But what if you’re a Matthew McConaughey type, and all this talk about faster faster faster just stresses you out, man? While most watchmakers are obsessed with upping the horsepower, there are brands going in the opposite direction. In 2013, the now-defunct Antoine Martin dropped the tortoise to Zenith’s hare. The $20,000 Slow Runner made news with a watch that runs at a comparatively plodding one Hz. Through the sapphire glass back you can see the massive balance wheel spinning left and right, and where that show can be frenetic on other watches, it’s almost calming on the Slow Runner. Grönefeld similarly makes a watch with a stuck-in-quicksand movement—the $82,000 One Hertz. These examples tend to be symbolic rather than practical. According to Antoine Martin’s founder Martin Braun, he designed the watch with the intention of “slowing down time.”
Breguet’s and Zenith’s pieces aren’t sold in huge numbers, so they’re more about those brands reasserting their reputations as legendary watch world innovators. Like Acura selling a 531-horsepower hybrid-engined NSX supercar alongside soccer dad sedans or Calvin Klein making runway statement pieces alongside boxer briefs, the value of the Hertz Race is having the cachet of a big breakthrough trickle down into brand perception, even if you’re not buying the supersonic timepiece at the top of the pile. And in the realm of watches, the quest for ever more good vibrations is a fun reminder that despite the smartphones and quartz movement dominance, something as charmingly old-world as a set of gears and levers can still be pushed to limits no one ever thought possible.