It’s incredible how our expectations influence our subsequent experiences; this was a point powerfully driven home to me recently as Stephen Forsey proudly demonstrated Greubel Forsey’s Grande Sonnerie, a timepiece that the upmarket brand has been developing for well over a decade.

When Forsey activated the minute repeater, its crystalline chimes reverberated loudly and clearly around the room, easily drowning out the background noise of the busy lunchtime cafeteria on the other side of the walls of our conference room.

Impressively, the cathedral chimes remained audible as Forsey closed his palm completely around the timepiece in a (knowingly) futile attempt to silence the gongs.

Greubel Forsey Grande Sonnerie

It was an impressive demonstration, but I wasn’t truly shock-and-awe impressed because I expected nothing less from Greubel Forsey.

While a side-by-side comparison would be necessary to confirm this, my impression was that the Greubel Forsey Grande Sonnerie sounded comparable to the Audemars Piguet Supersonnerie in terms of both volume and tone . . . and it could easily be even better.

Greubel Forsey Grande Sonnerie

Superlative is the bar that the Greubel Forsey team set for itself, and a superlative sound is nothing more than I’d expect from this brand’s first chiming watch.

The remarkable sound of the chimes is no doubt helped by the titanium case, a rigid alloy that is becoming the defacto standard in chiming watches in which the quantity (volume) and quality (pitch) of the sound is the ultimate goal.

My heart doesn’t jump for joy when Usain Bolt runs 100 meters in under 10 seconds, and I’ll bet his doesn’t either. World-class excellence is simply what we have come to expect from both Bolt and Greubel Forsey. That doesn’t mean that I was blasé, but it would take a lot to surprise me.

Water resistance: tick

I wasn’t even blown away by the fact that the Greubel Forsey Grande Sonnerie is water-resistant to 30 meters. While that does highlight the fact that it sounds so good despite the normally audio-dampening effect of the rubber seals, especially compared to Patek Philippe’s chiming watches – which are only dust-resistant rather than water-resistant. There is also no mention of water resistance for any of Bulgari’s sonneries or F.P. Journe’s Sonnerie Souveraine.

So the Greubel Forsey Grande Sonnerie is ahead on kudos and increased reliability there.

Greubel Forsey Grande Sonnerie in titanium

Water resistance is an important factor in chiming watches. These watches are difficult to seal because of the case openings for activation pushers and/or repeater slides, and the motivation to seal is offset by the fact that seals prevent sound exiting from the case as well as moisture from entering.

A nice, loud chime in the here and now is a much easier sell than calculating reduced service costs in the future.

Greubel Forsey Grande Sonnerie on the wrist of Stephen Forsey

Moisture ingress in repeaters is especially a problem in the humid tropics − hello, Singapore − because air and moisture is being continually sucked in and out of the case when its wearer moves in and out of air-conditioned environments.

I’m surprised that consumers haven’t boycotted non-water-resistant chiming watches by now because of the expensive service costs they are likely to require.

However, the Greubel Forsey Grande Sonnerie isn’t the first to offer water resistance: there’s also the Audemars Piguet Supersonnie, though it’s only water-resistant to a less-than-super 20 meters and the Jaeger-LeCoultre Hybris Mechanica (Duomètre) à Grande Sonnerie, which is water resistant to a very impressive 50 meters.

But my experience is that the Greubel Forsey has significantly superior volume and tone.

Impressive, yes, but again I expect nothing less from Greubel Forsey.

Back of the Greubel Forsey Grande Sonnerie

Even the safety system automatically disconnecting the chiming mechanisms when the crown is pulled out to avoid accidental damage to the movement is nothing less than I’d expect from Greubel Forsey.

But I was by no means feeling blasé in front of such a technical and musical tour de force.

Impressively wearable case

I wasn’t impressed so much by the fact that the sound of the Greubel Forsey Grande Sonnerie’s cathedral chimes were as good, if not better, than any I have heard before (despite the 30-meter water resistance), but that the sound was so impressive in such a wearable case size.

Greubel Forsey Grande Sonnerie

At 43.5 x 16.1 mm, the asymmetric case of the Grande Sonnerie has practically the same measurements as the brand’s Tourbillon 24 Secondes Aysmétrique . . . and that’s despite the fact that the Grande Sonnerie has the same 24-second, 25-degree inclined tourbillon regulator as the Tourbillon 24 Secondes Aysmétrique PLUS an incredible 855 movement components in the movement alone (the case adds another 80 parts).

Greubel Forsey Grande Sonnerie in titanium

Sonneries are all about managing power

If the minute repeater is the queen of complications due to its complexity, then the grand sonnerie is king because it is even more complex. And managing the power is a complication by itself.

A minute repeater has a relatively normal winding system and mainspring barrel for the watch movement that isn’t affected by the chiming mechanism powered by the activation of a slide or pusher. The user manually powers the chimes each time they are sounded.

But a grand sonnerie is like a grandfather or tower clock that can, if desired, be silent, chime the hours (petite sonnerie mode), or the hours and the quarters (grande sonnerie mode).

The (considerable) power required for these chimes sounding many times per day are not supplied by the user at each activation like the minute repeater, but come from stored power. And it isn’t easy to store a lot of power for chiming functions in the cramped confines of a relatively slim watch with 855 components, including an inclined tourbillon and double coaxial barrels for the timing gear train.

Greubel Forsey has devised a hybrid winding system with manual winding for the watch movement offering a healthy 72 hours of power reserve. Manual winding here ensures the tactile connection between timepiece and owner.

View through the display back to the movement of the Greubel Forsey Grande Sonnerie with the large “mini” rotor to wind the chiming mechanism on the left

The spring barrel powering the chiming functions on the other hand is wound via a platinum mini rotor, though perhaps “midi rotor” is a more accurate description. This keeps the chiming spring wound for as long as the watch is being worn, and it has a healthy 20 hours of autonomy as well.

Movement side of the Greubel Forsey Grande Sonnerie

All to say that this is a Grande Sonnerie you can have the pleasure of listening to that is not only louder than most, if not all others, but will also play for much longer before needing rewinding.

In the chiming function is unlikely to require rewinding at all.

And there’s more . . .

That safety system automatically disconnecting the chiming mechanisms when the crown is pulled out is just one of 11 security systems ensuring that the Greubel Forsey Grande Sonnerie can be enjoyed with little fear of breaking something.

The speed regulator for the striking mechanism is silent, so no annoying whirr to distract from enjoying the music.

That voluminous, melodious sound is thanks to a specially developed titanium acoustic resonance cage.

Unlike the majority of minute repeaters, when the Greubel Forsey Grande Sonnerie chimes minutes with less than three quarters (anything under 45 minutes past the hour), there is no pause where one, two, or three quarters might have sounded if required. The minutes chime immediately after the hours and quarters no matter how many, if any, quarters there are.

And, again, I’d expect nothing less from Greubel Forsey.

One of the two cathedral gongs is visible at the top of the case band window offering views to the 24-second tourbillon of the Greubel Forsey Grande Sonnerie

And in a nice touch that is unlikely to be noticed unless you are “in the know,” those two cathedral gongs that wrap around near the top of the movement are not perfectly circular, but rather shaped to follow the asymmetric bulge of the tourbillon. You can see one of the one-piece gongs through the case band window onto the tourbillon and the other looking from the top of the dial to below the outer edge of the tourbillon bridge.

Greubel Forsey Grande Sonnerie in titanium

But perhaps the greatest feature of this Grande Sonnerie is one that is virtually invisible due to how well it’s been integrated: architectural balance. All of the indications on the dial – the open tourbillon, the hammers visible dial side at 10 o’clock, the crown with integral minute repeater pusher, and the case band strike function selector pusher at 4 o’clock – are all logically, harmoniously, and ergonomically arranged as if the incredible complexity within posed absolutely no constraints.

Notice how the sonnerie power reserve indicator bulges out of the case slightly to visually balance the bulge of the tourbillon 180 degrees on the other side.

Note how the small seconds subdial compensates for the “bite” taken from its dial by the tourbillon opening by way of a double-ended hand of two different lengths pointing to concentric 180-degree markers of 30 seconds each.

Consider how the strike mode function indicator is retrograde rather than rotating 360 degrees.

Greubel Forsey Grande Sonnerie

I suspect that it didn’t take Greubel Forsey 11 years to make this Grande Sonnerie sound so good or to develop the multitude of failsafe mechanisms, but to make this – one of the world’s truly great timepieces – look like it effortlessly fell into place.

I really didn’t expect to be overly impressed by Greubel Forsey’s Grande Sonnerie because I was fully expecting to be blown away, and anything less would have been disappointing. But I have to admit that I was both blown away and very impressed.

The Audemars Piguet Supersonnerie set a high bar for grandes sonneries, but it is to all intents and purposes a work in progress, an experimental platform if you will. The Greubel Forsey Grande Sonnerie is a fully finished production piece as refined (both technically and visually) and as polished (both technically and visually) as no other.

It truly is in a class of its own.

Greubel Forsey Grande Sonnerie front and back

For more information, please visit www.greubelforsey.com/en/collection/grande-sonnerie

Quick Facts
Case: 43.5 x 16.1 mm, titanium with white gold pushers and crown, convex display back and asymmetrical case band window onto tourbillon, 30-meter water resistance
Functions: hours, minutes, small seconds; petite and grande sonnerie, minute repeater on demand by crown-mounted pusher, strike mode selection by pusher (grande sonnerie/petite sonnerie/silence), striking power reserve indicator, movement power reserve indicator
Movement: hand-wound movement with patented 25-degree inclined 24-second tourbillon, two patents pending, 11 movement safety mechanisms, automatic winding (platinum mini rotor) for striking mechanism, two coaxial series-coupled fast-rotating barrels, security system disengages strike mechanism if crown pulled out, one-piece cathedral gongs on three levels, dedicated striking barrel maximizing hammer force and striking power reserve (about 20 hours in grande sonnerie mode), no quarters pause in striking rhythm, 855 components (movement only), superlative hand finishing
Price: 1,150,000 Swiss francs (excluding VAT)