Overview
A ratchet or rattle, more specifically, cog rattle is a musical instrument of the percussion family and a warning/signaling device. It operates on the principle of the ratchet device, using a gearwheel and a stiff board mounted on a handle, which rotates freely. Variants include the gragger used in Judaism, the rapach, and the raganella.
Method of playing
The player holds the handle and swings the whole mechanism around. The momentum makes the board click against the gearwheel, producing a clicking and rattling noise. A popular design consists of a thick wooden cog wheel attached to a handle and two wooden flanges that alternately hit the teeth of the cog when the handle turns. Alternatively, smaller ratchets are sometimes held still or mounted and the handle turned rapidly by the player. The mounted ratchets allow for greater control of the duration and timing of the sound. This allows the ratchet to be used like a snare drum, placing sustained rolls in precise durations of time. Dynamics are controlled by the rate at which the ratchet is rotated.
Uses
In Jewish tradition
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