MusicReasonChords and Harmony
How much did the voices actually move?
Enter two voicings of the same size, in any order. This tool matches each voice from the first to a voice in the second by the assignment that minimizes total movement, then reports each voice's signed motion in semitones, common tones, and the total. It never claims a lower total is artistically better; that judgment depends on musical context.
Answer
Understand
Comparing two voicings only makes sense once you know which note in the first voicing corresponds to which note in the second; without explicit voice labels, this tool finds the pairing that minimizes the total distance every voice travels, the same underlying idea music theory calls smooth voice leading. A shared pitch between the two voicings should always be recognized as a common tone with zero movement, not paired off with some other note by coincidence.
Worked examples
Moving from C4-E4-G4 to B3-D4-G4, the shared G has zero movement, correctly recognized as a common tone rather than reassigned. Swapping which voicing is first and which is second reverses every voice's signed direction while the total absolute movement stays exactly the same, confirming the comparison is symmetric.
Method and limitations
The tool tries every possible one-to-one pairing between the two equal-sized note lists and keeps whichever pairing has the smallest total absolute semitone movement, preserving full octave data throughout rather than reducing to pitch class. When more than one pairing ties for that minimum, the result is marked ambiguous rather than silently picking one. This launch scope supports small voicings only (a handful of voices), since trying every pairing grows quickly with voice count; it never asserts that a smaller total movement is a better musical choice, only that it is a smaller number.
The minimum-movement assignment is a genuinely useful default precisely because it is not always the musically intended one: a composer may deliberately want a particular voice to leap rather than take the smoothest available path, and comparing the assignment this tool finds against the pairing you actually intended can itself be informative, revealing when a "smoother" alternative pairing existed that the music chose not to take.