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MB&F Launches an Insanely Complex Chronograph, the Legacy Sequential EVO (Live Pics & Price)

One movement. Two chronographs. Multiple timing modes, including split-seconds and lap timer.

| By Brice Goulard | 8 min read |
MB&F Legacy Sequential EVO Chronograph Split Seconds Lap Timer Stephen McDonnell

In 2015, MB&F assigned the Northern Irish independent watchmaker Stephen McDonnell a mission: reinvent the perpetual calendar mechanism and counteract a major issue inherent to most LM watches, a centrally positioned, dial-side balance wheel. The result: the groundbreaking, innovative and unprecedented Legacy Machine Perpetual. Seven years later, MB&F presents the result of a second challenge given to McDonnell: a chronograph that had to be typically MB&F and like nothing else on the market. It was certainly worth waiting for because this is a chronograph like you’ve never seen before. It’s a chronograph that does far more than just measure simple elapsed times, a chronograph that isn’t constructed like a classic chronograph, a chronograph that couldn’t be more Legacy Machine and that is named MB&F Legacy Sequential EVO. 

Behind the Legacy Sequential EVO is one of MB&F earliest friends, Stephen McDonnell. It’s worth recapping a thing or two about Stephen McDonnell. For starters, he isn’t Swiss but was born in Northern Ireland. He didn’t start as a watchmaker but studied theology at Oxford University’s Pembroke College from 1992 to 1996. As a result, he has a very different perspective when it comes to creating watch movements. Less “preconceived” if you want. Thus, when Max Büsser asked him to reinvent two of the most classic complications, the perpetual calendar and the chronograph, he took an out-of-the-box approach that involved going back to the drawing board and looking at these complications in a completely different way. No preconceived ideas, new solutions… The first vision of his work came to life with the Legacy Machine Perpetual. The second one is this out-of-this-world chronograph, the Legacy Sequential EVO.

The idea is simple. Being a trained theologist, McDonnell took a rather simple and highly pragmatic approach. Instead of looking at the mechanical side of things first, he thought about all the ‘whats’ or possibilities a chronograph could offer, about all the events you could time with it, and about all the situations where a chronograph could be used. Having listed all these timing possibilities, he then started to work on the ‘how’…

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MB&F Legacy Sequential EVO Chronograph Split Seconds Lap Timer Stephen McDonnell

The Complexity of the Legacy Sequential EVO

What is the Legacy Sequential EVO? In (very, very) short, it’s a double chronograph, with two independent but still linked chronograph mechanisms, two column wheels and no fewer than five pushers, all built around a new mechanism named the “Twinverter” switch, allowing this watch to have more than one timing mode. It is a chronograph, but it’s also a twin chronograph to time two independent events, and it’s also a split-seconds chronograph, and finally, it’s a lap-timer watch too. The dial features chronograph displays, each with its own 60-second and 30-minute counter. Each of these chronograph displays can be started, stopped, and reset independently, using the respective start/stop and reset pushers on the sides of the case. So far, this accounts for the four pushers… But there’s a fifth one, located at the 9 o’clock position, actuating the Twinverter. This is the secret behind the Sequential EVO.

MB&F Legacy Sequential EVO Chronograph Split Seconds Lap Timer Stephen McDonnell

All in all, there are four different modes, in addition to the classic use of a single chronograph side:

  • Independent mode – measures the duration of multiple events with separate starting points and endpoints, even when the events overlap in timing
  • Simultaneous mode – measures the individual duration of two events that start simultaneously but have different endpoints
  • Cumulative mode – measures the individual cumulative duration of two discontinuous events
  • Sequential mode or lap-timer – measures the individual sub-duration of a single continuous multi-phase event, with provision for sub-durations that last over a minute

MB&F Legacy Sequential EVO Chronograph Split Seconds Lap Timer Stephen McDonnell

As we hinted, the trick behind this unprecedented movement is the Twinverter, which controls both chronograph systems, operating as a binary switch that inverts the current start/stop status of each chronograph. This means that if both chronograph displays happen to be stopped (at zero position or otherwise), pressing the Twinverter will cause both of them to start simultaneously. If they are both running, the Twinverter makes them stop. If one is running and the other is stopped, the Twinverter stops the one that is running and starts the one that is stopped.

MB&F Legacy Sequential EVO Chronograph Split Seconds Lap Timer Stephen McDonnell

Back to the modes… Simultaneous mode is used, for example, in a race involving two competitors, starting simultaneously. The Twinverter allows both chronographs to start at exactly the same time, but the different endpoints can be easily recorded by pressing each chronograph’s individual start/stop pusher. Cumulative mode frequently occurs in the work environment, where you might want to know how much time you spend on two separate projects as you switch between them throughout the day. By starting one chronograph when you begin working on one task and then using the Twinverter when you shift focus to the second task, you can easily track the amount of time you cumulatively spend on each task. This mode is also particularly practical for a chess match.

MB&F Legacy Sequential EVO Chronograph Split Seconds Lap Timer Stephen McDonnell

Sequential mode (or lap-timer) makes sense in competitive sports, where it can be used to measure individual lap times. Starting one chronograph at the beginning of an event and using the Twinverter upon the completion of a lap instantly launches the second chronograph in order to time the next lap, while the first chronograph is stopped. The stopped chronograph can then be reset to zero, ready to be relaunched with the Twinverter for the following lap. Finally, Independent mode can be used, for instance, in the preparation of a meal, where different things need to be cooked for different periods of time, at different points in time. Here, you operate the two chronograph mechanisms via their respective pushers.

Best to understand how the different modes of the Legacy Sequential EVO actually work is to look at the video below:

Using the EVO Concept as a house for the chronograph

Having created a movement with so many functions related to daily life and sports activities needed a resilient watch case. Luckily, the case already exists at MB&F and has already housed one of McDonnell’s movements… And that is the EVO case that was introduced in 2020 with the LM Perpetual EVO.

This new sub-collection within the LM lineup is all about wearability, robustness and versatility, with a more contemporary approach to the design and to the materials. As such, the 44mm case is now more angular and features new lugs that can integrate a purposeful rubber strap. Also, no more gold or platinum here, but a case made of zirconium, a metal known for its silvery-grey deep lustre, lightness and durability – it’s lighter than steel and more durable than titanium. Coupled with these exceptional properties, its hypoallergenic and anti-microbial attributes make it ideal for an active lifestyle watch.

MB&F Legacy Sequential EVO Chronograph Split Seconds Lap Timer Stephen McDonnell

While some elements of the LM collection have been reutilised, such as the (almost) no bezel construction and the ultra-domed sapphire crystal, there are some important features. First, the case is equipped with a screw-down crown and is water-resistant to 80 metres. Second, it features a so-called FlexRing, an annular dampener fitted between the case and movement, providing shock protection along both vertical and lateral axes. Machined from a single block of stainless steel, the dampener imparts exceptional robustness to the movement within.

Through the sapphire bubble, one can see the hallmark elements of all LM watches, including the top-positioned oversized balance wheel and its arched bridges, executed as always with great care and bercé polishing. Underneath are the indications and dials, with the chronographs taking centre stage. The indication of the time is relegated to an almost secondary position, at 6 o’clock in a sub-dial. Then, symmetrically placed underneath the balance wheel are the chronograph counters; each of the independent timing modules has its own 60-second and 30-minute counters.

MB&F Legacy Sequential EVO Chronograph Split Seconds Lap Timer Stephen McDonnell

The MB&F Legacy Sequential EVO is launched in two editions. First is an atomic orange model, with the movement’s mainplate coated in orange CVD and all sub-dials coated in black. This model is worn as standard on a black rubber strap. The second version is slightly less polarising and more monochromatic, with the mainplate coated in coal-black (black PVD) with all the dial elements in black and white. This version is worn on a white rubber strap as standard – the black one will certainly be available too.

MB&F Legacy Sequential EVO Chronograph Split Seconds Lap Timer Stephen McDonnell

Turning the Legacy Sequential EVO over, you can admire the back of the movement. Although it might not have as many parts to show as the front, it still makes an impact. Designed and finished in a typical MB&F way, with large polished anglages, rounded bridges, gold chatons and thick Geneva stripes, the bridges are coated in grey NAC for more contrast. The pinnacle of this reverse side is, to me, the two oversized and ultra-light wheels that seem to float above the movement. The decoration is impeccable; it shows impressive attention to detail and an incredible antique charm. A power reserve indicator is placed on the movement side. This hand-wound movement, the 20th of MB&F, comprises no fewer than 585 components, boasts 72 hours of power reserve and beats at a 3Hz frequency.

MB&F Legacy Sequential EVO Chronograph Split Seconds Lap Timer Stephen McDonnell

Availability & Price

The MB&F Legacy Sequential EVO Chronograph, either in atomic orange or coal-black, is released as part of the permanent collection and isn’t limited (production will be limited by the manufacturing capacities of creating such a complex watch). It is available now, including on the brand’s online boutique here. The price before taxes is CHF 160,000EUR 160,000 or USD 180,000.

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