Jaeger-LeCoultre · Master Grand Réveil
The movement in detail
The movement’s idea
A watch can remind you of the time through touch. Jaeger-LeCoultre’s Master Grand Réveil combines a mechanical alarm with a perpetual calendar, with a selector for ringing or vibration. In this 74-second CREATIVE TIME video, we explain the principle using close-up footage and animated diagrams.
The alarm has its own energy store: a separate wound spring in a barrel. As the watch runs, the mechanism tracks the chosen alarm time. When that time arrives, the alarm trigger operates. The stored mechanical energy powers the signal.
In ringing mode, a small hammer strikes a gong. Vibration mode provides a tactile reminder on the wrist. Both belong to the mechanical alarm; this principle requires neither an electronic vibration motor nor a battery. An indicator on the dial shows the selected mode.
Practical meaning
The dial brings together several complications: a perpetual calendar, a four-digit year display and moon phases for both hemispheres. This explains its busy appearance: it is an instrument with several ways of communicating time.
What interests us is the connection between mechanics and sensation: time can be seen, heard and felt. A vibration alert is particularly useful for a personal reminder on the wrist. We do not measure its strength in this episode or compare it with modern electronic devices.
The diagrams are schematic: they explain energy storage and the hammer-and-gong principle rather than the exact arrangement of components. Technical checks used the Master Grand Réveil manual and the account of this model in the Background of the Invention section of patent US7896542B2. The different construction proposed later in that patent is not presented as this watch’s mechanism.
Script, editing, graphics and sound design: CREATIVE TIME. Footage comes from the supplied video; Russian narration was synthesised from a new script. Time in detail.
