MusicReasonChords and Harmony
How is this chord split between the hands?
Choose a chord, a voicing family, and left/right register targets. This tool allocates the chord's declared tones between hands under that family's own rule, and checks that no left- hand note ends up sounding above a right-hand note.
Answer
Understand
Different piano voicing traditions split a chord's tones between the hands differently. A shell voicing keeps only the root in the left hand and the color-defining third and seventh in the right. A rootless voicing removes the root from both hands entirely, common when a bass instrument already states it. A close-position voicing simply stacks every declared tone in one hand's compact reach.
Worked examples
A Cmaj7 shell voicing at left-hand octave 3 and right-hand octave 4 puts C alone in the left hand and E, G, and B in the right hand, confirming the shell's defining third and seventh are both present. A rootless voicing of the same chord drops the left hand's C entirely, leaving only E, G, and B, still fully identifying the chord without restating its root.
Method and limitations
The chord's tones come from the same locked chord-formula vocabulary Chord Builder uses. Each voicing family declares which chord-degree numbers belong in the left hand; every other declared degree goes to the right hand at the chosen upper register. The tool then checks that the highest left-hand pitch never sounds at or above the lowest right-hand pitch, and that the family's required tones (the third and seventh, for shell and rootless families) are present. It makes no claim of universal stylistic correctness beyond these declared range and non-crossing checks.
Choosing a low left-hand octave and a high right-hand octave leaves the most room between hands and is the safest way to avoid a crossing warning; pulling both octaves close together, especially for a shell voicing whose left hand plays only the root, is the most common way to trigger one. A close-position family stacks every declared tone into a single hand's compact reach by design, so it has no separate left-hand register to check against and will never report a crossing on its own.