1. Connect one hand, release the other
Purpose: give simultaneous lines different connections without changing their shared timing. Preparation: play each articulation separately with an easy hand and a steady pulse. The marks below are editorial practice choices in an original study.
The RH slurs group four quarters at a time. Aim for a connected line within each slur and a small, deliberate release at its end. The LH quarters are detached: shorten their sounding length without making the next attack early.
Establish the contrast
- Play the RH alone and sing its two small phrases. Let the phrase endings release without an exaggerated gap.
- Play the LH alone, leaving a small silence after each note while retaining the quarter-note pulse.
- Combine the hands at a moderate, comfortable pace. Listen for RH gaps that appear whenever the LH releases.
- Exchange the articulations as a variation: LH connected, RH detached. Keep pitches and rhythms unchanged.
A staccato dot does not prescribe one exact percentage of a note’s duration in every context. For this drill, choose an obvious but comfortable contrast. Reduce the difference later while preserving independent control.
Check: the detached hand should not become automatically louder. Separate the questions “how long?” and “how strong?” before trying to control both at once.
2. Put accents in different places
The LH emphasizes beats 1 and 3. In the first bar, the RH emphasizes the F on beats 2 and 4 within a connected eighth-note line. Those accents need not pull the other hand into the same pattern.
Keep the pulse under the accents
Tap the LH pattern while speaking all four beats. Add the RH rhythm on a tabletop, then play the pitches. Begin with small dynamic differences: an accent is relative prominence, not a demand for a hard attack.
The second bar removes the RH accent marks while the LH keeps its pattern. Let the RH settle into a phrase ending. Do not continue accenting mechanically after the written pattern stops.
Separate three controls
Timing: keep each eighth note in place. An accented note should not arrive early merely because it is stronger.
Duration: maintain the RH connection inside its slur. An accent does not automatically shorten the note.
Balance: let the hands keep different degrees of emphasis. If every LH accent becomes a RH accent too, simplify the RH to repeated notes before restoring its contour.
Variation: move the RH emphasis to its off-beats on repeated eighths while the LH retains beats 1 and 3. This is an unprinted coordination variation; do not transfer its accents into a repertoire score unless the phrase supports them.
3. Make contrasting articulation serve the phrase
Return to the Invention No. 13 excerpts in the preceding chapter. Choose a short segment where one voice has running sixteenths and the other has longer notes. Hear the rhythm and direction of each before deciding how connected they should be.
Compare two versions
In the first version, connect the running figure and gently separate selected longer notes in the other voice. In the second, use a less pronounced contrast. These are listening experiments, not claims that Bach prescribed either version. Preserve all ties and rests, and avoid shortening notes whose sustained duration is essential to another voice’s movement.
Record both at the same tempo. Prefer the version that makes the motives and phrase direction clearer without sounding clipped or heavy. The appropriate degree of separation will also depend on tempo, instrument, room, and musical context.
Keep phrase endings independent
One voice may finish while another continues. Practice the ending voice alone, then add the other line through that release. Avoid a shared breath that interrupts the continuing voice unless the music calls for one.
Where a voice starts again after a rest, prepare its next position during the silence while the other hand continues. The rest belongs to the rhythm; it is not permission to delay the next entrance.
Final check for this group of chapters
Play a short polyphonic passage and ask: which voice leads, which notes remain sounding, which line releases, and where does the next entry occur? You should be able to answer those questions from both the score and the sound.
Practice dose: a few attentive repetitions of one overlap or release, followed by the complete phrase. Stop when the intended contrast becomes reliable; further repetition without listening can replace an independent articulation with a habitual one.