Review: Armin Strom Dual Time GMT Resonance Manufacture Edition Black

Our hands-on review of the Armin Strom Dual Time GMT Resonance with exclusive live pictures and resonance explained. Price CHF 95,000

At the forefront of independent watchmaking, Armin Strom consistently delivers watches that showcase both horological innovation and exceptional craftsmanship.

The Swiss manufacture has become a reference in the pursuit of mechanical resonance for increased precision. Through resonance, two balances oscillate in opposite directions and synchronise over time, averaging out errors for greater accuracy.

The benefits are threefold: more stable timekeeping, improved energy efficiency similar to a cyclist drafting behind another, and reduced sensitivity to external shocks, helping the rate remain steadier.

Before examining the brand’s latest resonance model, it’s worth noting the key milestones that led to its creation.

In 2016, the first generation of the Mirrored Force Resonance (our review can be read here) introduced the patented resonance clutch spring, developed and produced in-house. 

This sophisticated spring connected two sets of oscillators so they influenced each other and eventually synchronised at a preferential frequency. 

In 2018, the Masterpiece 1 Dual Time Resonance housed two independent movements to display two independent time zones beating in resonance. 

In 2022, the second generation of the Mirrored Force Resonance, reviewed here, further refined this technical breakthrough and enhanced its aesthetics.

Combining the Mirrored Force Resonance approach with the dual time concept from the Masterpiece 1, Armin Strom introduced the Dual Time GMT Resonance First Edition in 2024.

We recently had the pleasure of wearing and testing the second edition of this model, the Dual Time GMT Resonance Manufacture Edition Black, first unveiled at Watches and Wonders Geneva 2025. 

Spending time with it on the wrist gave us the opportunity to admire its mechanics and see how naturally it integrates advanced horology into daily wear. We are now delighted to share our exclusive pictures and impressions.

At the heart of this timepiece is the hand-wound ARF22 calibre operating at 3.5 Hz (25,200 vibrations per hour). Entirely designed, engineered, and manufactured by Armin Strom, it is the eighteenth in-house movement from the independent watch brand. 

Two independent oscillators synchronise in anti-phase through the natural phenomenon of resonance. 

In this process, the oscillating mechanisms exchange vibrational energy, influencing and mutually regulating each other’s rate. Armin Strom achieves this by linking the twin balance wheels with a pulsating clutch spring that transfers vibrations efficiently and ensures they oscillate in harmony. 

Wound via the crown at 4 o’clock, the calibre also incorporates two separate gear trains to drive the two displays independently, each with its own day/night indicator. 

Thanks to the ability to adjust the two time zones entirely independently using the two crowns positioned on either side of the case, you can set time zones that deviate from GMT by fractions of an hour, such as New Delhi’s 30-minute offset. 

This is something that very few GMT watches permit. In fact, most dual time movements allow independent adjustment of the hours only, and only a few support half-hour settings. Here, both hours and minutes can be set independently on each dial, offering true flexibility for global travellers. 

During our time with it, we also repurposed one display to measure elapsed time, which the watch can track from one minute up to 12 hours — ideal for timing a meeting session, an excursion, or even the duration of a flight.

Under the sapphire crystal with anti-reflective treatment, the synchronised motion of the balance wheels and the pulsation of the resonance clutch spring create a compelling kinetic spectacle. To see this captivating effect in action, watch our Instagram reel.

The twin balance bridge is crafted from steel with a perfectly flat surface that is hand-polished to a mirror finish, in accordance with the highest standards of traditional haute horlogerie. 

The two symmetric time dials feature a black grenage finish, surrounded by snailed black chapter rings set with applied polished baton indexes that complement the faceted hands. 

The engraved and mirror-polished sun and moon indicators, set on 24-hour wheels mounted directly on the movement, provide practical day/night information while lending a touch of refinement.

The ratchet click system delivers a pleasing animation on the dial side during winding, turning a functional operation into a point of interest. 

The winding experience itself is very satisfying, thanks to a mechanism that connects to a pinion positioned between the two barrels to distribute the load more evenly. 

This two-part system, comprising a gear with Breguet teeth and a spring-loaded top element, promotes smoother engagement, more efficient energy transfer, reduced friction and improved durability of the winding train. 

The Dual Time GMT Resonance Manufacture Edition Black comes in a well-proportioned stainless steel case measuring 39 mm in diameter and 9.05 mm in thickness, with alternating satin-brushed and polished surfaces to emphasise the lines and a slim bezel that leaves space for the captivating dial. 

The case retains a discreet embossment at 6 o’clock as a nod to the Armin Strom “lip”, a signature of the brand originally designed to offer a surface for personalising the watch with engraved initials. 

Water resistance of 5 ATM (50 metres / 165 feet) adds versatility. 

Paired with a glossy taupe alligator strap secured to the wrist by a double-folding clasp elegantly engraved with the recurring brand's logo, the watch sits nicely and comfortably on the wrist (for reference, the one in our pictures is 17.8 cm / 7") thanks to its compact case and ergonomically designed lugs.

Through the transparent sapphire crystal caseback, more elements of the 231-part movement come into view. 

Its symmetrical architecture is accentuated by the mirrored arrangement of open bridges and gears. 

The engraved main plate outlines the specific characteristics of the Mirrored Force Resonance in raised text. 

Two skeletonised mainspring barrels can be observed as they wind simultaneously, providing a power reserve of up to 42 hours. 

The finishing is impeccably executed in the tradition of Haute Horlogerie: hand-polished bevels, screws, and countersinks, complemented by circular graining, perlage, and Geneva stripes. 

The interplay of anthracite and silvery tones enhances depth and contrast across the movement, rewarding close inspection.

The Armin Strom Dual Time GMT Resonance Manufacture Edition Black, reference ST25-DT.90, is a limited edition of 50 pieces with a price of CHF 95,000.

The watch embodies Armin Strom’s resonance philosophy while remaining practical for daily use. Its dual displays with independently adjustable hours and minutes, combined with a compact case, demonstrate ingenious engineering without compromising wearability.

Experiencing the ARF22 Calibre in action — with its twin balances oscillating in synchronised motion, the tactile pleasure of winding, and the refinement of its finishing — confirms it as a fully realised expression of the brand’s innovative concept.

Ultimately, the Dual Time GMT Resonance stands as a benchmark of contemporary independent watchmaking: a technically sophisticated, precisely engineered timepiece that unites innovation, craftsmanship, and everyday practicality.
arminstrom.com