Exploring the Valjoux A05.291 Movement: A Technical Overview

For the first time, Tissot incorporates the Valjoux A05.291 movement, specifically designed for the new PR516 Chronograph Mechanical. The Valjoux A05.291 movement represents the very high-end of Tissot offering. Derived from the Valjoux 7753 caliber, the A05.291 is a manual winding variant that showcases remarkable precision and durability.

The A05.291 has undergone specific modifications to fit the PR516 and its heritage. The automatic winding block has been removed and replaced with a new, specially decorated bridge, that shows the inscription “TISSOT 1853”. Furthermore, the mainspring is fitted with a fixed bridle instead of a sliding one, allowing for a complete lock when fully wound. The movement’s dimension is of 30.00 mm and a height of 7.285 mm.

Valjoux A05.291 movement floating in a blue skyValjoux A05.291 movement floating in a blue sky

Power Reserve and Barrel Architecture

One of the most notable features of the A05.291 is its impressive 68-hour power reserve. This extended duration is achieved through a newly designed barrel architecture. The benefit for the wearer is significant - the watch can comfortably last an entire weekend without the need for winding, a convenience that brings both practicality and peace of mind.

Another key attribute of the A05.291 is its resistance to magnetic fields, a crucial factor in maintaining accuracy in today’s gadget-filled world. The incorporation of NivachronTM in the balance spring significantly reduces the impact of magnetic fields. This innovative material not only minimises stops and residual effects caused by magnetism but also ensures consistent performance in various environments.

The movement features ETA’s Chrono regulation system. One of the major advantages of eliminating the traditional index-assembly is to limit the influence of wear, and aging on accuracy over time, therefore, improving the long-term reliability of the movement. Moreover, this system does away with the traditional index-assembly, opting instead for laser-regulated precision. This advanced method ensures remarkable stability and accuracy, especially notable towards the end of the power reserve, a time when many movements lose accuracy. The Chronometer offers high precision. Operating at a frequency of 28,800 vibrations per hour (4 Hz), the A05.291 is designed for optimal performance. The Elaboré grade guarantees an average rate of 5 ± 5 seconds per day.

Moreover, this movement is also notable for its shock resistance, featuring the NIVACHOC A system. This system optimises the angle of the cone and the exclusive shape of its spring, ensuring effective shock absorption while maintaining excellent centering of the balance pivot. The simple cone design enhances the mechanism's reliability.

Equipped with hours, minutes, and small seconds displays, it also includes a chronograph function with 60-second, 30-minute, and 12-hour counters. The chronograph mechanism operates via a cam system with two pushers, providing reliable operation.

Close-up view of part of the Valjoux movement A05.291Close-up view of part of the Valjoux movement A05.291

Housing 25 jewels, the Valjoux A05.291 exemplifies Swiss watchmaking excellence. Its blend of a lengthy power reserve, antimagnetic features, precise regulation, and wide-ranging functionality not only appeals to watch aficionados but also positions the PR516 as a premium option in Tissot's lineup.