Joe's Blog

Two or more notes from one physical gesture, case 1: the ratchet

August 14, 2018

The principle of the ratchet.

There is a general category of motions that is capable of producing a series of sounds from one and the same continuous gesture.   This is of special advantage when playing very fast.

One example of this group is when a motion, though single and complete, occurs in small segments.

We start with a gradual and uninterrupted forearm rotation.  This motion is then broken up into parts by suddenly forcing the motion of the arm to come to a temporary and brief stop.  The result of this stopping is that the inertia of the rotation,  like water accumulating behind a dam, increases rather than decreases the force bent on continuing the motion.

At each such stop, one note is sounded, and then the rotation is permitted to continue.   This sequence of stopping the motion and then quickly continuing it, continues until the full course of the rotation is covered.  Depending on how one divides up the motion, the overall rotation will produce a series of notes ranging from a minimum of 2 to 3 notes to a maximum 8 to 12 notes.

The virtue of this procedure is that instead of making one motion per note, we have something that is more like one continuous motion that we attempt to resist.*

Each time the overall course of such a motion is temporarily arrested, the forward momentum that has built up until that point is first diverted into the production of a new note or sound.  Once that note has begun to sound, there is no longer any need for the restraint of the continuation of the overall rotation.  The note itself has acted like a brake or stoppage of the motion.  The more this stoppage persists the more a force builds up, like water behind a dam, until the motion forces itself to spill over the blockage (the note) and continue.

I call this type of overall motion that is broken down into a series of interruptions a “ratchet” like effect, after the rapidly repeated sounds made by the percussion instrument of the same name.

In future blogs I want to discuss many other types of motions that fall into the more general category of obtaining a series of sounds from the application of one motion (a motion that is sometimes interrupted as in today’s example, and sometimes flows continuously).

If you would like a preview list of all these motions, just let me know and I’ll post them.

* Like “pumping” the brakes of the car instead of jamming the brakes to the floor.  Or like the escapement of a Swiss watch that temporarily stops the main spring from unwinding, creating the sound of a “tick” or a “tock” and then lets the unwinding of the spring continue.

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