Fix one note. The recording is tracked for pitch and split into notes wherever the pitch holds for longer than 50 ms, each drawn as a bar on a piano roll at the pitch it was sung. Drag a bar up or down and only that span moves; the rest of the take is passed through untouched.
The piano roll
Rows are semitones, with every C labelled. A note’s bar sits at its measured pitch, which is rarely exactly on a line: a singer is a few cents off most of the time and that is what sounds human. A moved note is drawn solid at its new pitch with a faint bar where it was.
Tune all moves every note to its nearest semitone by the cents it was off. Reset clears every edit. Click an empty part of the roll to move the playhead and hear the result in place.
How a note is moved
The moved span runs through the same phase vocoder as the pitch shifter: each partial’s frequency is measured from how far its phase advanced between frames, multiplied by the ratio, and resynthesised with a phase that is never reset, so a shifted note is exact and does not flange. Between an edited note and the next, the ratio glides over the Glide time rather than stepping, which is what keeps the edge of an edit from clicking.
Edits are stored as spans in the link, only the notes that moved, so a take with three hundred notes and two fixes carries two entries.
Limits
The tracker follows one fundamental. Give it a lead vocal, a bass line, a horn or a whistle, not a chord or a mix. A note moved more than a fourth starts to sound like a different singer, because the formants move with it; for a larger move use the formant shifter after it to put them back. A run of fast notes may be read as one note if each is under 50 ms; the editor cannot split what the tracker did not separate.