Jaeger-LeCoultre

ektaylor
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First perpetual: a review of the 8-day master perpetual

My first (and likely last) perpetual. I very much like this complication since I am a scientist and it is essentially an analogue computer to track the major astronomical cycles: periods of the earth’s rotation (day), moon’s orbit around the earth (moon phase and, approximately, month), and the earth’s orbit around the sun (year). The complexity of the perpetual calendar mechanism is necessitated by the fact that these periods are not simple integer multiples of each other and mechanical corrections are needed.

In reviewing this particular PC (now out of JLC’s lineup, but we know the 876 caliber will be back), I will focus on the factors that differentiate it from the JLC MUT PC, since my choice was between these two.

1. Movement

Before taking ownership of this watch, my impression was that PCs that could only be set by individual pushers were much less user friendly than the Kurt Klaus-style adjustment, where everything is adjusted from a single pusher/the crown. In turn, the UN-style PC that adds the ability to change the date backwards represented a further significant improvement in usability.

Having pressed the pusher around 800 times to first set this watch, I’m no longer certain that the last two advances are so significant! Even if it’s not practically so useful, it is very cool that all adjustments are synchronized and I appreciate the technical sophistication of this adjustment style.

Apart from the Klaus-style adjustment (shared with the MUT PC), the major distinguishing feature of this PC is its eight day power reserve. This is enormously useful as it means I can interchange my watches with this PC, without having to set it again when I put it back on (as long as I wear it at least once a week, which so far I have).

Although this watch doesn’t have a second hand, from the position of the minute hand, I estimate that it’s gaining around 15 seconds per week, which is very good of course.

2. Case

Here’s where this model suffers in comparison with the MUT. The price you pay for an 8 day power reserve is the beefy case. Not sure how thick it is, but I would estimate 10 to 11 mm. Far from the elegant MUT case profile. I felt the long reserve and the slightly more interesting dial more than countered this deficiency, however.

3. Dial.

Although the MUT has a beautiful, symmetric dial, I find this one slightly more interesting, with its two miniature “sub-dials” at 11:30 and 12:30 for the power reserve and day/night indicator. There’s a lot going on with this dial, yet it remains highly legible. An extremely beautiful, mechanically evocative dial!

4. Backside

I don’t find the backside particularly beautiful, with only the balance wheel really visible, but I much prefer a manual wound movement to one with a full rotor.


In summary, I’m absolutely thrilled with this watch. I look forward to see what JLC comes up with next for this caliber.

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