This is the current Chronometre a Resonance, rebuilt in 2020 and offered at 40 and 42 mm. The case is 18K 6N gold, the dial plate is solid 5N gold, and the two registers are whitened guilloche silver as they have been since the model was introduced. What changed underneath is substantial: both trains are now driven through a constant force device, which addresses the one criticism the earlier generations attracted. It is the third version of the watch and the first that does not depend on the owner winding it regularly. The two registers keep the side by side arrangement that has defined the model since 2000. It is offered in gold and in platinum.
Warm on warm is the standard combination for the gold version and it makes the registers do all the work. A 5N gold plate against 6N gold case metal reads as one material at a distance and separates at close range, and the two silver discs are the only cool elements anywhere on the watch. Both are cut with guilloche and then whitened, and both are framed by polished steel rings screwed through the plate. Two case sizes are offered and the difference is more significant than the two millimeters suggest, since the dial furniture stays the same and the 42 leaves more empty plate around the registers. Which of the two suits a wrist is not obvious from a photograph. At 40 mm the dial is dense and the registers nearly fill the plate, which is closer to how the early watches looked; at 42 mm the composition opens up and the watch reads as more modern. Neither is a compromise, since the movement is the same in both and the case was drawn for each size rather than stretched. Lugs are short and curved, the bezel is narrow, and the profile stays thin enough that a watch holding two movements sits flat under a cuff, which is not something the size suggests. Both diameters are offered in every metal the current generation comes in, so the decision is entirely about proportion.
The constant force device is the reason this generation exists. On the earlier watches the two movements only stayed properly in step when both barrels held similar amounts of energy, which in practice meant winding daily and accepting that an example left in a drawer would not behave as intended. Journe solved that by putting a remontoir between the barrels and the balances, so each train receives the same force regardless of how much is left in the mainspring, and the two movements stay coupled through a full cycle. It is the same principle he has used in his tourbillons since 1991, applied here to a problem specific to resonance. A remontoir is a small secondary spring rewound at intervals by the mainspring, and its purpose is to give the balance the same push every time rather than a strong one when the watch is fully wound and a weak one when it is nearly down. On a single movement that improves the rate. On two movements that have to stay coupled it does something more fundamental, since the coupling itself depends on both balances swinging with similar amplitude, and unequal force is what pulled the earlier watches out of step. Solving it took the model from a demonstration that worked under the right conditions to one that works under ordinary use.
Three generations now exist and they are easy to keep apart. The first, from 2000, has brass movements and two matching twelve hour registers. The second replaced the brass with rose gold and later refined the way the two trains communicate. The third, from 2020, adds the constant force device, moves to 40 and 42 mm cases, and is the version currently sold. Journe has treated the model as an unfinished problem across all three, revisiting it rather than restyling it, which is unusual in a catalogue where most references were drawn once and left alone. It also means the generations are not interchangeable in the way dial variants are. An early Resonance and a current one share a principle and very little else: different movement material, different case sizes, different behavior when left unwound, and a different answer to the question the model was built to ask. Collectors tend to end up owning one from the beginning and one from now rather than choosing between them. For a buyer who wants only one, the current generation is the more usable object and the early ones are the more historically interesting, and neither answer is wrong. What is not in question is that this is the version that works as intended without any allowance being made for it.
This is the version to buy for use rather than for history. It holds its rate without daily attention, the case sizes suit modern wrists, and the mechanism does what the earlier ones aimed at without the caveat. What it gives up is the connection to the period when the brand was building watches by hand in very small numbers, which is what draws people to the early examples. Both sizes are offered in this metal. As a current reference the obstacle is allocation, and the choice between 40 and 42 should be made on the wrist rather than on paper. Everything else is settled by the specification. The gold version is the warmest of the current executions, the platinum is heavier and cooler, and the mechanism is identical across both. Servicing remains twice the work of a normal watch, which is worth knowing at the outset rather than discovering later, and the manufacture is the only realistic place for it wherever the watch is bought. Beyond that the model asks nothing unusual of an owner, which is a sentence that could not be written about any earlier generation of it.
