he DSTB 42 collection is enriched with two new editions. With this true-beat seconds model, Arnold & Son present a Mint Green dial in a red gold case and an Ascot Blue dial for the platinum version. Produced in a limited edition of 18 pieces, each combines asymmetrical displays and mechanical sophistication with its exceptional complication.

The grained dials, with their dense texture and vibrant shine, are adorned with three openwork gold bridges supporting the true-beat seconds mechanism, facing the off-centred white opal hours dial. This subtle interplay of textures and finishes demonstrates the depth of complexity and singularity that defines the DSTB collection.

The true-beat seconds was intrinsic to the marine chronometers that John Arnold supplied to the Royal Navy. Their escapements beat with the steady rhythm of one oscillation per second, naturally revealed by the seconds hand. With this clear, regular rhythm, Arnold & Son invented one of its most iconic complications: the true-beat seconds, also known as deadbeat seconds.

All true-beat seconds require a dedicated mechanism. No wristwatch escapement naturally beats at the rate of one oscillation per second, a frequency designed for certain large-format clocks. The A&S6203 calibre functions at 4 Hz or eight oscillations per second. Creating a seconds hand that jumps from one index to the next requires a dedicated mechanism, similar to an escapement. Developed in-house by Arnold & Son watchmakers and reserved for this collection, the mechanism is fully displayed on the dial side in tribute to the groundbreaking advances that John Arnold brought to marine chronometry.

This true-beat seconds mechanism is showcased in a manner befitting its historical importance for Arnold & Son. Choosing to position it on the dial side means the movement must be crossed, adding an additional level to the A&S6203 calibre and requiring the creation of three specific bridges. They are designed in harmony with the Arnold & Son style. Openwork and three-dimensional, they are crafted in solid gold.

On these bridges, the seconds hand follows the track stretching between 9 and 12 o’clock, providing balance opposite an off-centred hours and minutes dial in white opal at 5 o’clock. This layout reflects an intentional aesthetic choice, rather than merely a contrived offsetting of the movement, as indicated by the crown, which remains at 3 o’clock.

The operation of the true-beat seconds mechanism – even, steady, aesthetically pleasing – can be clearly seen. The counterweight of this quasi-escapement takes the form of an anchor, the foundational symbol of Arnold & Son. It moves in time with the calibre, precisely orchestrating the motion of the long, fine seconds hand.

The DSTB 42 is one of Arnold & Son’s most iconic lines and is based on the A&S6203 calibre, fully developed, machined, assembled and regulated at the Manufacture. This self-winding movement is powered by a 22-carat gold oscillating weight and offers a 55-hour power reserve. It beats at a rate of 28,800 vibrations per hour and, naturally, drives its true-beat seconds in 60 precise jumps per minute.

TECHNICAL SPECIFICATIONS

DSTB 42 Red Gold Mint Green & Platinum Ascot Blue Editions

Functions: hours, minutes, true-beat seconds

Movement:

• Calibre: A&S6203, mechanical self-winding
• Jewels: 32
• Diameter: 33 mm
• Height: 5.54 mm (8.33 on the bridges of the true-beat seconds)
• Power reserve: 55 hours
• Frequency: 4 Hz/28,000 vph
• Finishes: main plate: circular-grained, palladium-plated bridges: Radiating Côtes de Genève, chamfered and polished wheels: circular-grained, polished screws: blued and chamfered, polished heads oscillating weight: 22-carat gold. true-beat seconds mechanism: bridges in 18-carat gold, polished and chamfered

Dial: grained with PVD “Mint Green” or “Ascot Blue” treatmen

Case:

• Material: red gold 5N 18 carat or 950 platinum
• Diameter: 42 mm
• Thickness: 12.95 mm
• Crystal: domed sapphire with a double-sided anti-reflective coating
• Case back: sapphire with an anti-reflective coating
• Water resistance: 3 bar (30 metres/100 feet)

Strap:

• Material: Cornish green or ink blue alligator leather, hand-stitched
• Buckle: pin buckle in 18-carat (5N) red gold or platinum (Pt 950)

References:

• Red gold: 1ATCR.F01A.C1242A
• Platinum: 1ATCX.U01A.C0263X

Limited editions:

• Red gold: 18 pieces
• Platinum: 18 pieces

Swiss retail price

• Red gold: CHF 42,700 incl. VAT (subject to change)
• Platinum: CHF 54,600 incl. VAT (subject to change)