Grand Seiko

GRAND SEIKO’S 9SA5 movement, introduced last year, is one of the most significant technological advancements in a generation. This movement has been seen in several executions since, most recently on the SLGH007 (left). In terms of mechanical escapement design, there has been little that has successfully improved upon the base concept of the lever escapement, which has been around since 1755, and fewer still that were suitable for series production. (The Spring Drive, another Grand Seiko invention, was one of them and it is still popular today, over 20 years after its release.)

A notable feature of calibre 9SA5 is its Dual Impulse Escapement. Thanks to the shape of its pallet fork and escape wheel – both made using processes like those used in microprocessor manufacturing – it allows a more direct interaction with the oscillator, reducing the overall friction and enhancing efficiency. This contributes to the movement’s 80-hour power reserve, which is especially impressive considering its beat rate of four hertz.