Bulgari L’Ammiraglio del Tempo Minute Repeater is one of Bulgari’s most exciting technical masterpieces that is recently launched. Some may underestimate Bulgari as a ladies jewellery company, but we take note (with great pleasure!) that of late, Bulgari has shown itself to be a fierce contender in the world of haute horlogerie.
The Bulgari L’Ammiraglio del Tempo Minute Repeater
The Bulgari L’Ammiraglio del Tempo (Italian for Admiral of Time) Minute Repeater is created under Bulgari’s Daniel Roth line. Bulgari bought Daniel Roth and Gerald Genta from The Hour Glass in 2000. The initial years of ownership was in our view a bit chaotic and confusing. However in 2011, LVMH took a controlling stake in Bulgari, and since then they seem to have done a good job in aligning the collections. We are especially glad that they have retained a Daniel Roth line to showcase the ingenuity that Daniel Roth have traditionally put into his movements. And although Daniel Roth, the watchmaker is no longer in Daniel Roth, the brand, the L’Ammiraglio del Tempo Minute Repeater is a good tribute to his level of out-of-the box thinking.
The Bulgari L’Ammiraglio del Tempo is part of the company’s Daniel Roth line up, and hence bears the maker’s case shape and trademark design. The case is 47 mm wide, 50 mm long and 15.1 mm thick. The visual impact of the dial side is breathtaking. The cut out dial to reveal the constant force escapement and to show the hammers (yes, 4 hammers, count them!) with their gongs.
Case design
The Bulgari L’Ammiraglio del Tempo case bears Daniel Roth’s signature combination of round and rectangle. The case is rather generously sized at 47 mm in width, 50 mm in length and a thickness of the watch measures 15.1 mm. These dimensions may suggest a large watch, perhaps unwieldy on the wrist. But on wearing it, we found that it is very comfortable, fits snug on an average sized wrist. The titanium case we tried during our hands-on session, makes for a light case, but due to the massiveness and the weight of the movement still carries a nice heft. We are assured the pink gold version would be heftier, but still comfortable, but we did not have the occasion to try that.
The dial side is fascinating with the cut out dial to showcase the detent escapement, constant force mechanism, hammers and the resonant bars. Noteworthy is the perlage finishing on the cut out dial and the matching cut out hands in 18 k white gold.
Technical features
Detent Escapement
Bulgari L’Ammiraglio del Tempo Minute Repeater.
The Bulgari L’Ammiraglio del Tempo Minute Repeater is packed with technical feats. Firstly it uses a détente escapement, a form of escapement in the regulation system of a mechanical timepiece found historically in stationary clocks. Initially it was thought that this type of escapement is unsuitable for wear on the wrist since it is without shock resistance, and its inability to restart once stopped. The ubiquitous Swiss Lever escapement is robust and happily restarts once stopped. However, recent advancements have seen several manufactures introduce détente escapements in their movements. We have seen this in the Laurent Ferrier Gallet Micro Rotor, the Leroy Chronomètre à Tourbillon, the Urban Jürgensen 1140C and the Kari Voutilainen Détente Escapement Tourbillon. And now the Bulgari L’Ammiraglio del Tempo Minute Repeater joins the team.
Constant Force Escapement
Also interesting, and perhaps unusual is that the DR 7301 movement also uses a constant force system. This is implemented by the use of a remontoire which is inserted between the power flow of the movement train. Bulgari did not release technical data on where this remontoire is placed, but we hazard a guess that it is between the fourth and fifth wheel.
The remontoire is a spring inserted in the power path, and takes its power from the mainspring to wind itself up and discharges its power periodically to the next wheel on the train. In the DR7301, we speculate that this remontoire is placed between the power path of the fourth and fifth wheel, discharging once a second. Physically, this spring is shown by the yellow arrow in the photograph below.
The Bulgari DR7301 movement. The yellow arrow points to the spring sitting on top of the fourth wheel. This spring is the remontoire, charging and discharging once a second into the fourth wheel.
As the remontoire is much smaller than the mainspring, the fluctuations of its torque from being fully wound to fully discharged is smaller, approaching a constant torque (very small variations). See the diagram below to understand how the remontoire enables a constant force to be delivered to the escapement.
Power flow from a regular mainspring and from a constant force escapement.
It is interesting to note as well that Bulgari have chosen to use a cylindrical balance spring. We have also seen cylindrical balance springs in other watches, most recently in our review of the Leroy and JLC’s Spherotourbillons.
Another unusual aspect is that Bulgari have chosen a rather slow beat rate for the movement. It runs at 14,400 bph, when a classical movement beats at 18,000 bph, and a modern fast beat movement is typically at 21,600 bph or 28,800 bph. The use of the constant force escapement allows for this low beat to still achieve good chronometry.
Carillon Minute Repeater
Apart from all its visible complications, there is also a mysterious element to the watch. To those new to the watch, it may take quite a while to find the slide activator for the minute repeater. Turns out, its in the lower left lug. Ingenious. As a result, the lines on the case sides are clean and smooth…added benefit.
The repeating mechanism features a “hidden” slide activation system. The case features clean lines without the characteristic repeater activation system slide sticking out on one side. This makes for a great conversation starter given that those new to the watch may take quite a while to find the slide activator for the minute repeater. The activation slide is hidden in lower left lug on the case. The entire lug slide around the case, and starts the ball rolling for the watch to chime. A nice twist to the traditional, and well executed. As the lug can move, it cannot be used to anchor the strap, and Bulgari have crafted the case such that the strap attaches directly onto the caseback.
The minute repeater system is highly sophisticated. It features a full Carillon Westminster style minute repeater with 4 hammers. A typical minute repeater uses two hammers on two gongs and are able to strike two tones. In a carillon, the 4 hammers are able to strike 4 gongs which are then able to produce 4 distinct and separate tones. The generous proportions of the case allow the gongs to be very long, and the volume of the case allows the sound to properly reverberate and decay harmoniously, hence giving it the term “cathedral gongs”.
The Bulgari DR7301 movement. The repeating mechanism is fully visible through the sapphire case back. As can be expected, and visible in this photograph, finishing is top grade. The repeating mechanism is also very nicely laid out in a classical manner. Very pleasing to the eye.
How does it sound? Traditionally Daniel Roth and especially Gerald Genta have been excellent at making their repeaters sound clean, clear, and fairly loud. We remember somewhat fondly of the sonic capabilities of a certain Gerald Genta, which we thought to be spectacular, but was cased in a rather unfortunate octagonal case with ribbed sides. We digress. But with this as the backdrop and access to former Daniel Roth and Gerald Genta savoir faire, it is no surprise that the Bulgari L’Ammiraglio del Tempo Minute Repeater sounds quite superb. Each strike is clean, clear. The case dimensions allow the tonal character to develop fully, and harmonics to decay nicely into the silence as the last notes fade. Quite magnificent. And certainly a treat to the ear.
The hammers of the Bulgari L’Ammiraglio del Tempo. Note the specular polishing on the hammers. And the beautifully executed anglage on the edges.
Finishing
To the right of the detent escapement is a constant force system. It controls the power release such that power going from the mainspring to the rest of the movement is consistent over time.
As can be expected from a watch of this caliber, the finishing is immaculate. All the traditional finishing details are addressed. We particularly liked the beautifully executed specular polishing of the hammers as well as on many of the bridges. Even the countersinks for the screws are nicely chamfered and polished. We also loved the way the single arm on the balance cock is cylindrical, and polished to a high shine. This level of work is extremely demanding and requires a steady eye and a well coordinated hand of a master finisher.
The Bulgari L’Ammiraglio del Tempo wrist shot. Although the watch’s rather generous dimensions suggest otherwise, it sits very nicely on the wrist and is comfortable.
Overall, to say we are thoroughly impressed by this piece is an understatement. Given its technical mastery and quality sound, coupled with the stunning design aesthetics and quality finishing, the watch commands the stature of haute horlogerie and is fittingly priced as well. The Bulgari Ammiraglio del Tempo Minute Repeater in pink gold is S$490,000 and in titanium at S$ 475,000.
Bulgari L’Ammiraglio del Tempo Minute Repeater
Technical Specifications
CASE
50 mm titanium case with transparent back.Titanium crown with unique numbered sapphire plate.Unique lug activation system for Minute Repeater function.(Diameter 50.00 x 47.10 mm, Thickness 15.10 mm)
CALIBER
DR 7301 MANUFACTURE CALIBER WITH MINUTE REPEATER AND DETENT ESCAPEMENT
Mechanical movement with manual winding, Minute repeater with Carillon Westminster, 4 hammers & cathedral gongs, Detent escapement and Constant torque, Cylindrical ballance spring. Decorated by hand. 48 hours power reserve.
Limited edition of 10 pieces in titanium (to be released in September 2015) and 20 pieces in pink gold (released in 2014)
Frequency: 14’400 VpH (2 Hz)
Jewels: 56
Size: 38.00 mm, thickness: 9.38 mm
