Hands-On: The Greubel Forsey Double Balancier Convexe In 42.5mm Black Carbon
Last month, Greubel Forsey released a watch that I would argue is their greatest achievement to date: their Nano Foudroyante EWT, a 38mm flying tourbillon chronograph monopoussoir with foudroyante. That French word salad in a wearable case, with some of the best finishing on the market, is exactly the kind of thing that old-school Greubel collectors love. But newcomers to the brand were rater incredulous. That was not the kind of watch they think of when they think of Greubel Forsey. This, on the other hand, is another version of “peak Greubel” – the Double Balancier Convexe Black Carbon. And it’s great in its own way.
To be fair, when I took my appointment with the brand at Geneva Watch Days, this was the kind of watch that I was going to see. While Greubel Forsey has long made watches with traditional design language (what they simply call their “Collection”), they’ve also firmly established their Convexe line as a sportier collection for modern collectors. At just shy of $400,000, this new release is beyond the realm of most people’s wildest dreams, but sometimes it’s just fun to look at and to understand why.
I often approach watches with wide-eyed wonder and enthusiasm, especially when I see things from brands that rarely make their way to meetups or city streets. Because of that, I often like to gut-check my takes with Ben or other collectors, who have seen a lot of changes in the industry since the start of Hodinkee. Ben’s the one who told me that the “old guard” would have gone crazy over the Nano Foudroyante, and he’d know. In talking to Ben in the office recently about the brand, I framed the Convexe collection as “Richard Mille for nerds – the ‘if you know, you know, choice.'” He didn’t smack the idea down, so I’ll stick with that analogy.
Sure, Richard Mille has its own massive R&D wing at APRP, and they do technical innovation and manufacturing at scale in ways that Greubel Forsey (with only 260 watches or so made per year) can’t even dream of. I’d imagine that the fact that Greubel and RM compete for very similar price space has pushed Greubel to develop this kind of design more and more over the years, bringing us here. Richard Mille has made ultra-light materials a core component of their watchmaking, so if you were being reductive about the idea of saying GF is just following RM, the Carbon Convexe makes sense.
The Double Balancier Convexe Black Carbon is the latest iteration of a watch that first came out in 2022 as a 43.5mm by 14.35 mm titanium case. Last year, GF pushed the watch even further, shaving 1mm off the width while maintaining the same thickness now in a carbon case, limited to 22 pieces to be rolled out between 2023 and 2026. It’s a minor improvement, but it’s still important when you’re talking about a watch that’s shaped both front and back to better hug the wrist and emphasize the visual impact from the dial side. To do all of this is one thing – to do it in carbon is pretty remarkable.
The main part of the case, the main plate, and the main bridge are all made of carbon constructed by resin-impregnated layers of carbon sheets. All the layers are stacked in mold, heated, pressured, and cured. But because of the curve of this case, Greubel Forsey said they needed eight times the pressure normally used for shaped carbon cases – 16 tonnes per square centimeter. They also used extremely thin layers of carbon (1 to 5 microns per layer) to create a more tightly packed case, with fibers oriented to match the curvature.
This is one of the more impactful features of Greubel’s design ethos. A lot of brands would find ways to minimize how big their watch looks. Frankly, I think brands are still unsure of the right balance to strike for the market and hedge toward 40mm, but Greubel has done the reverse. The center line of the case from nine o’clock to three o’clock is noticeably thicker, which you can see especially when looking at the hour and minute markers on the rehaut. The hands as well are also incredibly curved to fit the display, which is even more obvious when compared to the flatter dial sections like the power reserve and mainspring barrel cover.
If not for the most recent Nano release, the GF Double Balance is probably the brand’s most mechanically interesting model. There are a number of takes on dual balance watches on the market, but what GF has done here is incline each balance with respect to the plane of the watch (and its natural gravity) and on different angles from each other.
The goal is to minimize positional errors and cancel them out through the differential, which also functions as a remontoire d’egalité. You can see the differential below, driven by the center wheel, constructed laterally with three co-axial wheels. The top and bottom wheels drive the pinion of the fourth wheels on its right and left.
You can see the remontoire d’egalité (above and below) on the front and back as spiral springs attached to the spokes of the top and bottom wheels. The springs wind every four minutes and release the energy in bursts to control torque and amplitude. But one thing you’ll notice above is that giant carbon mainplate.
There are things that Greubel puts attention into things that Richard Mille doesn’t – like traditional high-end finishing to the 9th degree. And yet, you can still get a watch that looks wildly sporty, modern, and eye-catching. Yes, this might not be the best example of that work. By making the main plate and so much of the rest of the watch in carbon, there’s not much movement left for traditional finishing techniques. You see it more on the front of the watch than the back, but it’s still there.
For all the technical marvels here, the biggest question mark might be the material itself. There’s something comforting about the repairability of metal cases; steel, gold, platinum – all of them can be fixed to some extent. If you know cars, you’ll know that the increased use of carbon across high-end sports cars has massive benefits but comes with major potential downsides. Only time will tell about how a case like this holds up over time (especially with things like chipping layers and delamination), but GF seems confident that their extra pressure and fine layering create a more durable product.
The rest of the touches make for a comfortable, wearable watch. I’ve got a 7.25″ wrist that fits the 42.5mm case size well. Sure, there’s depth to any case measuring 14+mm thick, but sometimes that’s the point. The Richard Mille – to go back to that well one more time – RM65-01 is a split-second automatic chronograph, but it’s also 16.10mm thick. With the GF’s rubber textile-textured strap and titanium and carbon folding clasp, you can strap it on and forget it.
If there’s one other nit to pick (besides the $400,000 price tag), it’s legibility. It’s something that I’ll admit I often forget to think about in the 5-10 minutes I get to photograph these watches. Yes, this is one of the lesser legible watches I’ve reviewed this year. I probably shouldn’t have saved that to the end. That said, I’m sure if you wore this watch for a few days or a week, you might start to get frustrated any time from 20 minutes to 50 minutes into the hour if you can’t see the minute hand quickly. But remember that photos aren’t real life – the movement of your wrist to check the time causes a shift in light and shadow in a way that will catch the hands. Then, you’re still looking down at one of the coolest watches a watch nerd could ask for.
Greubel Forsey Double Balancier Convexe Black Carbon, 42.5mm diameter by 14.35mm thick carbon composite case, with 50m water resistance. Openworked dial, showing the hours, minutes, seconds, power reserve, and inclined double balance movement with remontoire d’egalité. 72 hours of power reserve. Rubber, textured strap. Price: CHF 351,000, or approximately $400,000.
Hodinkee
