Urban Jürgensen Proprietary engine: the P5 movement in the Jürgensen ONE
In the final instalment of our trilogy on the Jürgensen ONE, we take a look at the beating heart inside the watch.
The Jürgensen ONE is an entirely new type of watch in the Urban Jürgensen collection and the movement inside it is, too. Whilst the majority of movements in the brand’s collection are based on its in-house P4 and P8 calibres (the latter available with or without chronometer certification), which are manually wound, the Jürgensen ONE is equipped with a new in-house automatic P5 calibre.
The P5 is essentially a self-winding version of the P4 base movement, which is already a great starting point in itself. The P5 is a robust, relatively large calibre at 32mm in diameter and therefore fills the case nicely, as can be seen through the transparent sapphire crystal case back of the Jürgensen ONE. It runs at 21,600 vibrations per hour and, thanks to two barrels, offers a power reserve of 72 hours, which is enough to get you through that all-important weekend break should you wish to switch your watch for something a bit more casual for the weekend. In keeping with the 246-year tradition of fine watchmaking at Urban Jürgensen, it also comes with a stop-seconds mechanism, which means that the time can be set with a precision down to the second whenever it needs to be adjusted.
© Urban Jürgensen
An open worked oscillating mass ensures that as much as possible of the movement is visible and that its superlative finishing can be admired. You can spend a fair while admiring the movement as you take in its hand finished chamfered edges and the radial Geneva stripe decoration, which has the centre of the balance wheel as its focal point. All the screws are blued and a long balance bridge securely affixed in both ends gives an unhindered view of the complete workings of the sprung balance assembly. A gold “UJS” shield and a 22-carat gold outer weight on the oscillating mass finish off the ensemble with a touch of luxury.
The GMT version of the movement is particularly noteworthy and is another example of the attention to detail from Urban Jürgensen. It has a clean dial layout with a home time zone sub dial in 24-hour layout – dispensing with day/night indicators as well. Søren Jenry Petersen, the company’s CEO, is an avid watch collector, and practicality is important to him. And as a man who has travelled frequently for business and continues to do so regularly, there is nothing worse than a complicated GMT watch. “You should be able to set the local time zone instinctively, without even looking at the watch, in the rather busy space of time you have between landing, remembering all your belongings – and getting off the plane.”
Jürgensen ONE GMT © Urban Jürgensen
The Jürgensen One is one of the few GMT watches on the market that allows you to do just that, by simply pushing one of the pushers integrated into the left-hand side of the case. Intuitively, pressing the upper pusher moves the main dial/local time forward in one-hour increments; pressing the lower one moves it backwards. You just need to know the time difference and you could even set the watch blindfolded – for example as you enjoy your final moments of fitful sleep on a long-haul flight. And any date changes are taken into account, too, whether you are moving the time forwards or backwards. All this is achieved within a tiny margin of just half a millimetre, in a movement that is 6.6mm thick, compared with 6.1mm for the three-hand version. This elegant solution ensures the case dimensions for the three-hand version and the GMT are the same.