amanico[JLC Moderator]
340448
Jaeger Lecoultre 2015 SIHH: Duometre à Spherotourbillon Moon.
Feb 17, 2015,00:09 AM
A question invaded my mind, when I saw the first pictures of the Duometre à Spherotourbillon Moon: Do we have a new Watch?
If we discuss the case, it is not really a novelty
The platinum case is, indeed the same than the Spherotourbillon introduced in the catalog in 2012.
The 2012 Spherotourbillon, in rose gold and platinum:
Same diameter, 0, 2 mm thicker for the" Moon ", we are very close... Till the moment you have a look at the side of the case at 9 o clock.
Here is located a window, to allow you to admire the ballet of the Spherotourbillon, and not only from the dial side.
But again, this is not a novelty, since this detail appeared with the Duometre à Spherotourbillon from the Hybris Artistica Collection.
The movement has a different reference: Cal 389, while the first Spherotourbillon movement was the Cal 382. When you look at them, they share the same dimensions ( 33, 70 mm big / 10, 45 mm high ), and a very similar look, backside and frontside.
Of course, we still have this dual wing construction, with one barrel dedicated to the regulating organ, and one for the Time. You will also find the Cylindrical hairsrping.
But when you read the technical spécifications, and when you compare them, then, you notice some différences.
The Cal 382 has a power reserve of 50 hours, while the autonomy of the Cal 389 is 45 hours. The Cal 382 is made of 460 parts, the Cal 389 has 476 parts.
There is no more date function in the Cal 389, but it gains a moonphase, on which we'll come back, for sure, when we discuss the dial.
The dial represents the major change. The aesthetics are still here, with the time at 3, the small seconds at 6 and the 24 hours at 12, without forgetting the Spherotourbillon, of course, and, as it is a Duometre, the two power reserves, one for the time, at 5 o clock, the other for the regulating organ, at 1.
A subtle change can be noticed if you pay attention to the location of the small seconds and 24 hours subdials. These zones are shaped like a hollow comma in the original Spherotourbillon, when they are outlined on the " Moon ".
Once again, this is not a new detail, since the outlined zones already existed in the Spherotourbillon Enamel from the Hybris Artistica collection.
Another element of style borrowed to the Hybris Artistica versions, the " stairway " leading to the Spherotourbillon.
The date around the dial dedicated to the time disappeared, like in the Hybris Artistica enamelled or sapphire versions.
This function has been suppressed to be replaced by the moonphase, which is the true novelty of this Spherotourbillon well named " Moon ".
The moonphase raises another important question. Basically, you have two kind of moonphases. Those who are accurate to one day each two years and a half ( Duometre à Quantiéme Lunaire ), or each 122 years ( Master Perpetual Celendar 8 Days, for example )..
Some exceptional moonphases are accurate to one day every... 1058 years. One well known example is the Lange and Sohne 1815 Moonphase.
What kind of moonphase do we have, for the Spherotourbillon?
The answer is... One day each... 3887 years, which seems to set, as far as I know, a new record for a wristwatch.
Which raises a second question summed in one word: WHY?
Indeed, it is most probable that no one of us will live so long to witness that kind of record, and even most probably, we'll have to set the moonphase way before, when the watch stops,
I asked Stephane Belmont to explain me the reasons behind this choice.
Here are his two answers:
1/ " The Duometre à Spherotourbillon Moon is an exceptional watch. If we opt for a moonphase, it has to be exceptional. "
2/ " You love Sports Cars? If yes, do you ALWAYS drive them to the maximum of their speed, or are you happy to just know that they have the ability to drive that fast? "
Another reason was spotted during our conversation, which is quite interesting. The Duometre à Spherotourbillon is dedicated to accuracy, with its barrel and geartrain feeding the regulating organ, and the tourbillon. Accuracy for the time, and now, accuracy for the moonphase, too.
The moonphase disc is made of lapis lazuli, for those who wondered. While german silver was used for the " stairway ".
Let's recall that one of the refinement of the Spherotourbillon is that its small seconds hand can fly back to zero, through the pusher at 2 o clock, without stopping the balance wheel.
What about some live pictures, now?
One picture I love a lot, featuring the magic of the Spherotourbillon, providing a feeling of life to the watch, and focusing on that window, on the side of the case:
And a last picture, showing the Cal 389:
So, you now get the idea behind the Spherotourbillon Moon. A sophisticated evolution of the previous model, borrowing some elements of style from the former versions, and pushing the concept of accuracy to another level, limited to 75 pièces.
Looking forward to your comments and thoughts,
Best.
Nicolas.
This message has been edited by amanico on 2015-02-17 00:23:58 This message has been edited by amanico on 2015-02-22 00:07:08