Real watch geeks are no doubt familiar with the Witschi machines used by watchmakers to measure the precision of a mechanical watch movement. The new Lepsi Watch Analyzer offers the same functions but in a portable luxury format that makes the perfect gift for this time of year.
Geneva-based company Lepsi has developed its own version of the measuring technology, which uses a high-precision microphone to capture the sound and vibrations emitted by the watch, and incorporated it into a small cushion that the watch can be attached to. The cushion, which comes in black or brown calfskin leather, can be connected directly to a smartphone or tablet and attached to a small stand. The watch’s rate can then be measured using the Lepsi Watch Analyzer application.
Once downloaded, the application is easily installed. It is currently only available for iOS devices, although an Android version is in development and WorldTempus has already had the chance to test it (the Android version takes longer to deploy because it has to be tested on all the main Android devices). Before the first measurement, a three-hour calibration process is required to determine the variation between your device’s internal clock and reference time signals from different atomic clocks around the world. During this calibration, the device must therefore maintain a strong Internet connection, so it is best not to move it.
Since your phone or tablet’s time signal remains stable, the calibration only needs to be done once and the variation from the time provided by the atomic clocks will remain constant. The application itself is then very simple to use and can measure the mean daily variation in rate of any mechanical watch in the six positions commonly measured: dial up, dial down, crown up, crown down, crown left and crown right. The position is changed simply by rotating the cushion in its stand or rotating the stand itself.
In its basic mode, the application gives a mean daily variation across all six positions and awards the watch up to four stars, depending on the precision of its movement (from 0 stars for a variation of over 40 seconds per day up to four stars for a variation of +/- 5 seconds per day). Lepsi’s co-founder Davy Pillet has tested 300 different watches using the application, 90% of which have shown precision levels within +/- 20 seconds a day and 50% to within +/- 5 seconds a day.
Activating watchmaker mode shows a greater level of detail, including the amplitude and beat error familiar from the Witschi machines. It also allows a greater degree of control for the user, for example allowing the periods of calibration and measurement to be set individually. Although the default measurement period is 30 seconds, a tourbillon escapement, for example, should be measured for at least 60 seconds to allow for one complete revolution of the tourbillon cage. The frequency of the escapement and its lift angle are determined automatically but the lift angle can be adjusted if required and the application provides a full list of the common lift angles used by most major manufacturers in its online user manual.
After analysis in all six positions, an average daily variation is calculated and can be stored in the application along with the name, description and photo of the watch. Subsequent measurements for the same watch can therefore be added to the application to show the history of each watch’s accuracy over time. A report can be created for each measurement and sent by e-mail.
To prove that its Watch Analyzer is capable of the same repeatability as its closest competitor from Witschi, the Chronocube, Lepsi tested the same watch 30 times in succession in the same position (to ensure the best possible stability of the watch’s rate) on both devices and averaged out the results using a formula to account for short-term variations in the watch’s rate over the 90-minute testing period. The repeatability figures for rate variation and amplitude for both devices were similar.
The compact design of the analyzer means that it can easily be carried anywhere, whether on a business trip, holidays or even on the bedside table. Its ease of use will appeal to any true watch nerd, who will be unable to resist constantly checking the performance of the different watches in his or her collection.
The Lepsi Watch Analyzer can be purchased online from Lepsi and costs 1,299 Swiss francs (1,099 euros or 1,349 US dollars).