This week’s Watches and Wonders show features the first appearance of a Japanese manufacturer at the show’s in-person event in Geneva. Grand Seiko – launched in 1960 by parent company Seiko as a producer of high-end watches – is also in town to announce its very first mechanical complication watch: the Kodo.
Japanese speakers will have picked up the name Kodo, which translates to heartbeat. It is an allusion to the distinctive tic of the mechanism, a world first in watchmaking, in which a tourbillon and a constant-force mechanism are combined into a single unit.
For Akio Naito, President of Seiko Watch Corporation, the Kodo is the latest attempt to cement Grand Seiko’s international reputation among aficionados as the “Japanese Rolex”. Naito, who promises more such mechanical marvels, first addressed the Grand Seiko brand’s perception issues in 2016, after speaking to colleagues and retailers in the United States, Seiko’s biggest market. Seiko outside of Japan.
Just 20 copies of the £309,360 Kodo will be available across the Americas, Europe and Asia over the next two years. Seiko Holdings, the parent company of Seiko Watch, reported last year that exports to the United States accounted for just 7% of net sales, with Europe and Africa accounting for 9% combined.
Justin Koullapis, partner of pre-owned watch retailer The Watch Club, as well as technical editor of the journal of the British Horological Institute and watchmaker for over 30 years, explains the combination of a tourbillon and a constant-force escapement in one single component is “an extremely technical achievement”.
“It’s also extremely esoteric, as it has only to do with improving timing and nothing to do with creating an illusion of complexity – it’s the exact opposite of style over substance. There’s no has had only a few forays into the same field, notably by the late English manufacturer Derek Pratt, as well as Francois-Paul Journe and Andreas Strehler, but none have been as well resolved as the Grand Seiko design.
Simply put, a tourbillon is a mechanism in which the escapement (the component that allows the steady “output” of power from the mainspring) is contained within a rotating cage to reduce the inaccuracy caused by the movement remaining too long in the same position – a system originally devised for pocket watches by the 18th century Cornish maker John Arnold.
The constant force aspect, on the other hand, refers to a secondary mechanism that provides the escapement with a smooth and constant flow of power as the mainspring relaxes. It usually takes the form of a chain drive which, although it does its job, is fundamentally flawed by comprising several tiny but power-hungry components.
The Kodo overcomes this by combining the tourbillon and the constant force mechanism into a single component – meaning there are no wheels or other parts in between and therefore no change in torque. transmitted to the balance for a period of 50 hours after the complete winding of the watch.
Grand Seiko has unveiled a concept version of the Caliber 9ST1 movement – originally called T0 – in 2020, by which time it had already been in development for eight years. But it wasn’t expected to appear in a production watch for quite some time, if at all.
“It was necessary to redesign 340 parts of the T0 movement to allow it to be used in a production watch,” explains Rob Brook, Grand Seiko UK brand manager. “The purpose of producing it now is to showcase Grand Seiko’s technical know-how. During the 50 hour period that the constant force mechanism is fully functional, the watch will remain accurate to 0.3 seconds per day.
The watch was created by a specialist team of movement designers and master watchmakers based in the Shinshu Workshop in Nagano prefecture in Japan. The 43.8mm case is made from a combination of platinum and hard titanium, with both materials polished to a distortion-free mirror finish using a method known as zaratsu. The strap on which the Kodo is mounted, meanwhile, is in hand-painted calfskin with urushi lacquer, an ancient technique used in the manufacture of samurai armor.
If the integration of the tourbillon and the constant-force mechanism is impressive to watch, it is also intriguing to listen to. As the inner tourbillon carriage rotates smoothly, the balance wheel vibrates at a steady rate of eight beats per second, while the outer constant-force carriage moves at one-second intervals, resulting in a peculiar tick set to a double eighth note.
“I insisted on getting the perfect sixteenth or sixteenth note feel so the owner could fully enjoy the watch,” says Kodo designer Takuma Kawauchiya. “Maybe it’s because of my passion for music and being a professional guitarist before joining Grand Seiko.”