Grand Seiko Kodo Constant-force Tourbillon

The Grand Seiko SLGT003, better known as the Kodo Constant-force Tourbillon (€370,000), is at once totally unexpected and completely expected. The brand stands on a decades-long history of building eminently practical watches; however, it boasts of innovations that show real flair such as the Spring Drive calibre and, more recently, the revolutionary dual-impulse 9SA5 movement.

An openworked watch with a darkly contemporary finish, the Kodo’s signature is its constant force carriage that sits directly over the tourbillon. This direct interaction confers performance benefits, but is also visually – and aurally – compelling; the balance wheel beats eight times a second while the tourbillon rotates, and over it all the constant force mechanism discharges once a second. The result is a rather hypnotic 16th note rhythm with emphasis at the top of every measure. The Kodo will be available as a limited edition of 20 from October this year.