RHY.11:4.4.1 - Keep a common time while allowing different actions

For a pulse with independently chosen accents, first distinguish the time being maintained from the movement used to maintain it. A regular pulse has recurring events at the required intervals. Its producing movement can accelerate, slow down, reverse and redistribute effort within each interval. A brush circle and a standing leg’s pressure–release need not have constant instantaneous speed or force.

Give both actions one recoverable temporal relation. Establish the beat, phrase or other reference that the passage uses, and locate the accent relative to it. Hear, speak, demonstrate or represent the combined result with its actual gaps. An accent halfway between beats must remain halfway between them; placing it on the next beat changes the result. When an external metronome supplies the pulse, the performer’s accent cannot physically alter that pulse. When the performer also produces the supporting movement, the actions share bodily resources and can disturb each other. The external reference can expose that disturbance while the performer constructs the joint action.

Prepare the accent within the continuing action. Choose a realization whose preparation and recovery fit between the required events. Keep the supporting movement going while the other contribution approaches its target. Start that approach early enough for the intended sound, contact or weight event to arrive at its chosen place. If the accent is late because its excursion takes too long, begin the preparation earlier or use a smaller feasible excursion while preserving the required articulation. Starting every preparation on a beat is unnecessary when the accent belongs elsewhere. A demonstrated combined phrase can make these overlapping preparations recoverable.

Allocate effort according to the two results. Give the accent a controllable means of articulation: a local change of pressure, a stroke, a free-limb movement or a different already available technique. Avoid recruiting a whole supporting movement merely because it makes the accent easier. For example, a short stroke can articulate while the other hand completes its sweep; an unloaded toe contact can articulate while the standing leg continues its pressure–release. The actual technique must preserve balance, contact, sound and continuation. Compensating changes of effort may help preserve the pulse: useful coordination does not require every part of the body to remain physically unchanged.

Correct the contribution that missed its target, using the intended relation. Attend to the pulse before and after the accent as well as to the accent’s place. If only the accent was late, change its preparation or articulation; do not make its accidental arrival the next starting point of the pulse. If the supporting cycle lengthened, restore that cycle against the selected reference and inspect the accent again. If both drifted together, their mutual agreement alone can hide loss of the musical reference. RHY.10 supplies a permitted phase or tempo correction when the whole reference actually needs to change. During a dense passage, act through the familiar coordinated movement and assess a short trace afterwards instead of trying to issue a separate conscious command for every muscle.

Keep choices available within a feasible range. Move the next accent to another required place while retaining the support. Later change the tempo or reference as the passage requires, and relocate the accents accordingly. This retains the useful timing connection while reducing interference between the actions. A technique that works only at one habitual phase needs further development if the intended use demands other phases. If an accent requires the same support, space or recovery time needed by the next pulse, change its means or the performing arrangement. Removing a required accent or moving it to an easier beat does not satisfy that version of the task.

This is selective coupling in the practical sense: share the timing that the passage needs, while controlling preparation, articulation and correction so that one contribution does not impose its unwanted changes on the other. A performer may organize a familiar combined pattern as one action or use more separately controlled contributions; the description does not require one particular internal clock. RHY.12 develops the missing coordination through practice of this joint result.

The same construction can be tried beyond a particular instrument when the receiving activity has a continuing temporal contribution, a separately variable articulation, means to realize both, and feedback that distinguishes their two errors. Singing a varied phrase over a beat gesture is one such use. A machine can realize comparable timing requirements through scheduling and suitable actuators, but its control implementation and qualification are engineering work. Matching the requirements supports reuse of this construction; it does not transfer an already acquired human skill.