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Review – The A. Lange & Söhne Tourbograph Perpetual Pour le Merite (Spoiler Alert: It is MEGA)

| By Brice Goulard | 12 min read |
A. Lange & Söhne Tourbograph Perpetual Pour le Merite - Review SIHH 2017

No need to beat around the bush… Some subjects don’t really need to be debated. The new A. Lange & Söhne Tourbograph Perpetual Pour le Merite is a superlative watch, a proper masterpiece, mixing all the technical marvels of one of the best manufactures in the world (because for once, it’s outside Switzerland), with a strong respect to traditions and a devotion to what is (to me, at least) the most important in a watch; precision. Yes, you could say that the Tourbograph Perpetual Pour le Merite blows things out of proportion but still, whatever the critics will be, we all must admit that this watch is, in every aspect, mega.

The latest of a long lineage

Back in 1994, 4 watches marked the resurrection of a manufacture named A. Lange & Söhne. This early collection included the Lange 1 (a watch that is still in the catalogue and that can be considered as the cornerstone of the collection) and the Tourbillon “Pour le Merite”, actually the first wristwatch to combine a tourbillon regulator with a fusée-and-chain transmission. Later, in 2005, it was followed by another watch combining these two complications, and additionally featuring a split-seconds chronograph (also named a rattrapante), the Tourbograph. This watch remained as the manufacture’s most complex timepiece until 2013.

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A 2010 Honey Gold version of the A. Lange & Söhne Tourbograph Pour le Merite

Indeed, in 2013, A. Lange & Söhne came at the SIHH with 2 extremely complex watches. The first one is the 1815 Rattrapante Perpetual Calendar, and as you’ve guessed by it’s name, it features a split-seconds chronograph with a perpetual calendar. This watch alone is already a very complicated piece, which features 2 of the 4 main complications the Tourbograph Perpetual has. Yet, in 2013, A. Lange & Söhne has another watch, this time the best the manufacture has ever done, the Grand Complication. This watch, a masterpiece priced at 1.9 Million Euros and produced in 6 examples, will remain a untouchable grail that few will have the chance to even see or handle once. Yet, as indicated by its name, it was the combination of a chiming complication (in this case a grande and petite sonnerie, as well as a minute repeater), a perpetual calendar and a split-seconds chronograph.

Finally, in 2016, A. Lange & Söhne came to the SIHH with another impressive piece, the Datograph Perpetual Tourbillon, based on the iconic “Dato” Chronograph Flyback, with a perpetual calendar and, hidden on the back, a tourbillon. This watch is clearly impressive but what you’ll see today is even more, as not only you’ll find the same complications (tourbillon, chrono and QP) but with a constant force device and a rattrapante… Yes, that’s a lot.

An almost Grande Complication

As complex this new A. Lange & Söhne Tourbograph Perpetual Pour le Merite is, it can’t officially bear the name “grande complication”. Indeed, in watchmaking, and besides what some manufactures will try to sell as such, a Grande Complication refers only to the combination of 3 complications, which are a split-seconds chronograph, a minute repeater and a perpetual calendar. And if you can add anything you want to that concept, the absence of one of these 3 complications simply ruins the idea.

Because it lacks a chiming function, the Tourbograph Perpetual can’t be named a Grande Complication. However, don’t see this as a real issue. Indeed, as impressive such watches are (they are so complex that only handful of manufactures have some in their catalogue. Even Patek doesn’t have one), they are based only on display functions. The chronograph, the QP or the repeater have nothing to do with the precision of the watch. They don’t intervene in what certainly is the most complex of all research fields, chronometry. However, the Tourbograph Perpetual adds to the QP and the rattrapante two complications that are useful to the very essence of a watch, its precision – in this case a tourbillon and a fusée-and-chain, these two combined offset two disruptive phenomena in a mechanical movement: gravity and waning spring force. To me, this is as impressive as a grande complication.


The A. Lange & Söhne Tourbograph Perpetual Pour le Merite proudly expose a tourbillon on its dial, in an aperture at 6 – which is not round but shaped not to interfere with the QP sub-dials. It’s actually quite difficult to say and some will call me posh, but this tourbillon regulator certainly is the most expected feature of the Tourbograph. Indeed, it’s not a first for Lange, whom watchmakers master this type of regulator for more than 20 years (the 1994 inaugural collection already featured a tourbillon). Ok, let me go back on earth and keep things real. It’s a tourbillon, and that alone is already an extremely desirable feature. However, when you consider all the rest around the tourbillon, it becomes much more impressive.

In the case of the Tourbograph Perpetual, the tourbillon is a classical 1-minute version, with screwed balance and balance spring manufactured in-house, and beating at the classical frequency of 3Hz (21,600 vib/hours). One stunning feature of the tourbillon is actually its bridge on top. At first, you think it’s the same as all Lange watches, with the same black-polish finish. Well, in fact it’s much more complex. Compared to the 2005 version, the base movement remains the same, and thus the tourbillon sits at the same depth into the movement. However, for the 2017 version of the Tourbograph, a perpetual calendar module has been added on top of the movement, meaning that the tourbillon sits lower compared to the level of the dial.

For that, watchmakers at Lange had to imagine a curved bridge. The finishing applied on it, named black-polishing (the most complex and time-consuming type of polishing) is being applied for the first time on a curved surface, making it even more complex. This might a small feature for most of non-watchnerds, real connoisseurs of fine watchmaking will appreciate this. Finally, as you can see, the jewel-bearing of the tourbillon (on both sides) is done via a diamond, held in place by a polished and screwed gold chaton. A close inspection reveal a faultless decoration.

“Pour le Mérite” / constant-force Fusée-and-Chain

The second feature that is part of the Tourbograph is actually not easy to see, as hidden underneath of the parts that compose the chronograph (the main-plate of the movement is almost invisible). Yet, this is a great complication we’re talking about: a fusée-and-chain transmission, which explains the “Pour le Mérite” name of this watch. I’d say that it’s nearly sad that it can’t be seen, considering the beauty and complexity of this function, alongside its implication in the great chronometry of this watch.

As we’ve seen, the Tourbograph Perpetual is equipped to fight gravity with its tourbillon. It is also equipped to fight waning spring force by providing a more constant force to the escapement. The combination of these two is properly magical (and rare in modern watches). The fusée-and-chain is a complex device that aims at creating a more constant force delivered by the barrel to the escapement of the watch, smoothing the torque that is received by the escape wheel over the whole length of the power reserve.

The 636-part chain, the cone-shape pulley (fusée) and the barrel of a Lange “Pour Le Mérite”

A fusée consists of a cone-shape pulley, linked to a chain coiled round the barrel. The fusée features a spiral thread to receive the chain. Thanks to the increasing circumference of the thread, the diminishing force of the mainspring is compensated. As the mainspring unwinds, the chain rolls on the barrel and off the fusée. The increasing leverage of the fusée compensates for the waning torque of the barrel. The chain of the Tourbograph Perpetual comprises no less than 636 parts. The power reserve is 36 hours, as most “Pour le Merite” watches from the brand, even though it is now fitted with several additional complications.

Perpetual Calendar

This is the main novelty of this A. Lange & Söhne Tourbograph Perpetual Pour le Merite. It now features a perpetual calendar. Still, even if Lange has already several QPs in the collection, this one was not an easy task in terms of development. Indeed it comprises no less than 206 parts. Because the Tourbograph has a tourbillon and and a number of hands running on the dial, a classic perpetual calendar was not possible. Lange had to redesign the base calibre of the Tourbograph and to add a specific module (which was built around the tourbillon) on top to be sure that the interaction of the parts was perfect.

Even though the Tourbograph Perpetual features a massive load of complications, its display remains extremely simple and legible. Furthemore, it is very traditional to Lange’s production. The QP is based on 3 sub-dial, all comprising two indications (even though one is shared with the chronograph). At 12 is a classical moon-phase indication (with the moon being accurate for 122.6 years) and a date printed on the periphery of this sub-dial and pointed by a white gold hand. At 3 are the months and the leap-year, again displayed in a clear style. Finally, at 9 is a shared sub-dial, which serves as 30-minute counter for the chronograph and indication of the day of the week for the calendar (yet the hands are made in different material, as one is white gold and the other one is blued steel).

Rattrapante / Split-seconds chronograph

Last but not least of the 4 main complications of this Tourbograph Perpetual Pour le Merite is a rattrapante / split-seconds chronograph. This type of chronograph is the most complex of them all. A simple chronograph is already a challenge for watchmakers, as its development, assembly and adjustment are time-consuming, but the split-seconds version is on top of all the rest. It’s the ultimate chronograph (even if the Lange Double Split adds to this the flyback function, yet without all the rest the Tourbo has to offer).

What is a split-seconds chronograph? A normal chrono allows its wearer to time events, meaning to measure intervals of time. A split-seconds chronograph adds to this the ability to time intermediate intervals of time, meaning laps of a race for instance. How does it work? Instead of having one hand, a split-seconds chrono has two hands. When started, both are running jointly (one under the other). Yet, when the pusher at 10 is pressed, one of these two hands is stopped to display a intermediate time (the other one continues to run). Press again this pusher and the stopped hand will immediately catch up the main chronograph hand (which is why it’s called a rattrapante – which means catch up in French).

Technically, it requires not one but two column-wheels and much more levers and parts on the back of the movement, including a pair of clamps to stop only one of the two hands – a series of features that are so complex that they hide almost all the back of the movement, making the main plate, the fusée-and-chain or the tourbillon almost invisible. No complaints either, as the rattrapante chronograph mechanism is superb, with a complex tangle of levers, springs, wheels, brakes, clamps and column-wheels – and of course, all these parts are decorated with the highest level of details.

The Tourbograph Perpetual Pour le Merite itself…

Beside the addition of the perpetual calendar function, the 2017 Tourbograph shows several evolutions, compared to the 2005 version. First of all, the entire design has been discreetly modernized, by making it cleaner – main change is on the inner flange. Also, the case, only available in platinum (the old Tourbograph was available in platinum – 51 pieces – and in honey gold, in 50 pieces, launched in 2010). The guilloché central part of the dial found on the honey gold is no longer, for a sleeker look and mainly to compensate the more complex display of the 2017 version.

A. Lange & Söhne Tourbograph Perpetual Pour le Merite - Review SIHH 2017

Then, the case of the Tourbograph Perpetual Pour le Mérite is now 43mm (instead of 41.2mm) with a thickness of 16.6mm. The increase of size is mainly due to the presence of the perpetual calendar on top of the movement. The case is the same as most of the watches produced by A. Lange & Söhne, with a rounded bezel, solid lugs and brushed casebands. It is attached to a black strap with deployant buckle in platinum.


What to say about this watch expect that it is yet another masterpiece from A. Lange & Söhne. Once again, this watch is mega, and in all aspects: technology, complications, coherence of the association of the fusée-and-chain with a tourbillon, finishing (simply out of this world), beauty, relative discretion… I know some pointed out a certain exuberance, a lack of purity in this watch, just like the Datograph Perpetual Tourbillon, because it stacks as much complications as possible in a single watch. I don’t blame them. Still, the copy sent by A. Lange & Sôhne is a demonstration of its undeniable expertise. Few manufactures could have created this watch (really few… maybe a handful).

What critics could be made to the Tourbograph Perpetual? Its price maybe? At 480,000 Euro, it is indeed a grail. Yet, it doesn’t sound like unjustified, considering the watch you’ll get – and in any case, only 50 will be made. Its diameter? Well, it is for sure a large watch, a bit too large for my tastes. Yet, when you consider everything Lange achieved to insert in this watch, the 43mm diameter and the 16.6mm thickness are foolish. These complaints are so minimal that we won’t even notice them. There’s only one thing to do now, contemplate…

Specifications of the A. Lange & Söhne Tourbograph Perpetual Pour le Mérite

  • Case: 43mm diamater x 16.6mm height – 950 platinum – sapphire crystal on both sides
  • Movement: Lange manufacture calibre L133.1 – manually wound – 3Hz frequency – 36 Hours power reserve – fusée- and-chain transmission, tourbillon – 684 parts (chain counted as one part) – chain parts: 636
  • Functions: Hours, Minutes, One-Minute tourbillon, chronograph with rattrapante function; perpetual calendar with date, day, month, leap year; moon-phase display
  • Strap: Hand-stitched alligator leather strap, black – Deployant buckle in platinum
  • Reference: 706.025 – Limited to 50 pieces

2 responses

  1. Hi Brice,
    thanks for sharing this incredible timepiece. It is really breathtaking.


  2. As ever, I look in awe, admiration and desire at the beautiful work produced by A. Lange & Sohne. Indeed, these are Grail watches!

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