JLC Duometre à Sphérotourbillon SIHH 2012 Review

Amanico's comprehensive review of the Jaeger-LeCoultre Duometre à Sphérotourbillon from SIHH 2012 remains a vital resource for understanding this complex timepiece. His detailed exploration of its technical intricacies, aesthetic appeal, and the meticulous 'making of' process offers invaluable insights into JLC's high-horology capabilities. This article not only celebrates a significant release but also places it within the broader context of JLC's prestigious complications, making it highly relevant for collectors interested in the brand's innovative spirit.

If you allow me to paraphrase the famous advertizing about the Duometre, in this case I would say " One watch, Tow Chapters of the JLC Book ".

Clearly, the all new Duometre à Sphérotourbillon belongs to the Duometre family thanks to its original concept, but also to the category of prestigious watches, by its sophistication and its high level of finish.

How many pages have been written about high end watches, since the Gyrotourbillon in 2004!

The Gyrotourbillon One:



The Triptyque, in 2006:



The Gyrotourbillon Two, in 2007:



The Hybris Mechanica à Grande Sonnerie, in 2009:



The Master Grande Tradition Grande Complication, in 2010:



And the list is, of course, not exhaustive, as we could also mention the Minute Repeater, the Master Grande Traditinn à Calendrier Perpetuel and Tourbillon, the Extrem Lab One, the Reverso Platinum Skeleton Tourbillon.... And... The Duometre family, of course, whose first member is born in 2007, the Chronographe.

The Duometre à Chronographe:



The Hybris Mechanica à Grande Sonnerie, in 2009 ( pictured above ).

The Duometre à Quantième Lunaire, in 2010:



The Spherotourbillon is the fourth member of the Duometre family, and the latest offer in the high end JLC watches.

Being the latest doesn't mean that it is the less interesting, by far, as we are going to see, now, through the following points:

1/ The making of.

2/ The technical interest.

3/ The aesthetics.

4/ General thoughts.

I- THE MAKING OF:

I had the privilege, while at the Manufacture in December, to have a pre view on the Spherotourbillon.

It was not only a complete presentation, but also a visit to the different workshops in charge of this " opus ".

Attneding the making of is certainly the most interesting way to apprehend the high complexity of the Spherotourbillon.

Assembling the balance wheel and the cylindrical spring is a tough task.

The large 10 mm balance wheel, made of 14 Carat Gold, has to be perfectly balanced, which is the case if it turns in one direction, only.

If not, you have to remove some material from the inside part of the wheel, then check again, till it turns in one direction, only.

Finally balanced:



Then, you have to check that the spring and its two terminal curves is correctly shaped, which you can see with the help of a computer screen..

After you have to check that the spring is perfectly centred on the balance wheel.





The spiral is attached to the axis of the balance wheel by a collet, while the stud fix it to the cage of the Tourbillon.

Here, the outcome of the final assembly:



And here, a picture which shows how the balance turns:



It has to be said that all these operations are made by one person, who also worked on the Gyrotourbillon, the Cal 101, and some others movements, and that there is no laser sldering, but all manual work, here.

The second step is realized by the RGE Workshop, which stands for " Atelier des Réglages et Essais " ( Adjustements and Testing ).

Here, the prototypes are assembled, then tested by the prototypist, a watchmaker who will make all the necessary adjustments in the quest of the best precision.

The Prototypist at work:



The Prototype:





Abother view which hilights the very nice anglages:



The magic of the Spherotourbillon:



The first measures:



A view on the back side?

Once the movement is finely set, the production of the components for the series can start.

The Prototypist has another very important role, as he or she will train the watchmaker who will work on assembling the series, after the series production of case and movement.

The last step is, naturally, the assembly of the " final " watch at the " Spécialités Horlogères " workshop.

The modus operandi is logical: The watchmaker trained by the prototypist trains, in his turn, his or her colleagues at the " Spécialités Horlogères " workshop, under Mr Christian Laurent's authority.

This team knows the Duometre very well, as they already work on the Chronographe, and the Quantième Lunaire.

Those watchmakers do not only the whole assembly, they also do the internal testing before the 1 000 Hours Control, and will repair or service the watch themselves.

II- THE TECHNICAL INTEREST.

Of course, the Spherotourbillon shares with all the previous Duometre the Dualwing concept.

To make it short, one barrel and its gear train is dedicated to Time, while the other is dedicated to another complication

The Cal 382:



If the purpose of the Duometre is, by essence, accuracy, here, with the Spherotourbillon, precision reaches another level.

Two details, two informations:

- This is the first tourbillon adjustable to the nearest second.

The second stops when you use the pusher located at 2 o'clock AND flies back to Zero!

And this is possible WITHOUT stopping the regulating organ, whose energy comes from one of the 2 barrels, while the other is exclusively dedicated to the Time.

- The second important point is not visible, but it is very interesting: The Constant Amplitude.

In general, the amplitude can vary to 30 to 50 per cent.

The Spherotourbillon has a much reduced variation in amplitude. It has been prudently announced to 10 per cent, and on the prototype, Jaeger-Lecoultre measured it at 8 per cent, as you can see on the first measures posted above.

On the other Duometres, the amplitude line was flat till the 35 / 38 first hours, then decreased in a dramatic way.

The Spherotourbillon is a two axis tourbillon, with two different speeds of rotation ( 15 seconds for the first axis, 30 seconds for the second axis ).

Made of 105 parts, weighting 0, 518 grams, this spherical tourbillon has a carriage made in titanium grade 5,an aluminium stud holder, and beats at 21 600 vibrations per hour.

The Spherotourbillon:



The Cal 382 is 33, 70 mm big, and quite thick ( 10, 45 mm ) but a spherical tourbillon cannot be slim, by nature.

It has a power reserve of 50 hours, like the previous Duometres, and is made of 460 parts.

We said that accuracy was the main goal on this watch. And it is measurable!

On the prototype, it was measured at one second per day.

Better than that? The Gyrotourbillon One, which was measured at 0, 5 second per day!

III- THE AESTHETICS:

The Duometre lovers won't be surprised with this last iteration.

- You will see the traditional organization of the dial, which is divided in two:



On the right, the subdial dedicated to Time, surronunded by the Date, which is jumping from the 31st to the 1st.

This is an element of Design which is borrowed to the Hybris Mechanica à Grande Sonnerie, with some different functions ( Perpetual calendar and jumping hour, for this last one ) :



On the left side, the Spherotourbillon, " dancing " through the openworked dial which lets show some very nice anglages.



Then, on the bottom and on the top, the small second, the Time Reserve de Marche indicator, the second time zone, and the regulating organ Reserve de Marche indicator.



Duality... The perpetual envouting ballet of the Spherotourbillon, and the quiet progression of Time.



Do you also notice that it is the first time we have a no foudroyante small second on a Duometre, but a traditional one?

And, of course, you will find the sublime white grained, which is now part of the Duometre DNA.

- The case receives the classic finish of the Duometre, with the polished upper parts and the brushed sides.

The dimensions are still reasonable, with a diameter of 42 mm, and a height which is limited to 14, 1mm.

14, 1 mm is thick, in the absolute, but keep in mind that, by nature, a spherical tourbillon needs some space to move.

Here a view on the case side, showing the nice crown, too, which will allow you the set the time ( first position ), and the second timezone ( 2d position) when you pull it.



- The case back offers a superb view on the movement.

The Cal 382, like its elder brothers ( Cal 380: Chronographe / Cal 182: Hybris Mechanica à Grande Sonnerie / Cal 381: Quantième Lunaire ) is superbly decorated, with the now traditional Cotes Soleillées, and is recognizable to its two barrels.



Its mainplate and bridges are decorated and finished by hand.

Its level of finish is superior to the Duometres à Chronograph and Quantième Lunaire, with some superb and deep anglages.

Another view on the Cal 382:



The heated blue screws and the 55 jewels give a nice chromatic touch to the warm german silver movement.

And because a watch is also a serious buckle, let me say that I am very happy to see that the Spherotourbillon comes with a superb pin buckle, whose inspiration was obviously taken from the vintage world, with the famous applied JL Logo.



IV- GENERAL THOUGHTS.

So, what to think about the Duometre à Spherotourbillon?

An exceptional watch it is, for sure, for its level of finish, for the concept ( like any other Duometre, by the way ), for the magic of its spherical tourbillon, even if such a tourbillon is also shared on the Gyrotourbillon One and Two, and for its coherence, which is, to me, the sum of the qualities previously mentionned.

Now, the question is to try to appreciate it with its elder spherical brothers.

The Gyro One was a spectacullar watch, with a strong character ( you love, you hate, but it doesn't leave you indifferent ) and it has to be reminded that it was a Grande Complication.

The Gyro Two was an ode to the Spherical Tourbillon, with a very high level of quality, an eye catcher. I will always remember my first feelings when I saw it for the very first time.

The " Spherotourbillon " is more discrete, colder if I may say.... somehow ... Intellectual, a bit like the Quantieme Lunaire.

You first have to understand what is the concept behind, to be able to fully appreciate it, hence the choice I made to first speak about the context and the making of, before showing some pictures.




The " Spherotourbillon " offers something the Gyro Two offered with difficulty... The wearability, and a very nice, elegant case, which is the biggest flaw of the Gyro One, even if I could live with that, due to my unconditional love for that watch.

The thing which gives me a lot to think with the " Spherotourbillon " is the level of finish on the other Duometres... When I see such nice anglages on the " Sphero ", I regret to not see some of these efforts on the others...

I know, I know, the price tag is not the same as the " Sphero " is 4 to 6 times higher ( 200 000 Euros in Rose Gold ) than on the Quantieme Lunaire and on the Chronographe....

But when you see that...





... It is difficult to not wish the same on the Chronographe or on the Quantième Lunaire.

I wouldn't end this post without adding something about the alledged coldness of the " Sphero ".

Till now, I showed you some pictures of the Rose Gold version.

If you find the rose gold a bit cold...



What will you say when you'll see the platinum version, the only one to be in a limited series of 75 pieces?











Metal apart, the other notable difference between the Rose Gold and the Platinum is that on this last one, the cylindrical ^spiral is blue heated... Cherry on the cake.

For me, according to my personal tastes, I would not describe the " Sphero "as a cold piece, but better, as an understated " under the radar " watch, which is an evidence of good taste, of maturity, of self confidence.

Which one do you prefer?





The Spherotourbillon is the piece of the year, in the 2012 offer from La Grande Maison, and maybe from the other brands?

We'll see that later.

Looking forward to reading your thoughts and comments,

Best.

Nicolas