MusicTechHelpGuy walks through cleaning up a quantized bass line in Logic Pro, starting with how to pick the right grid resolution based on where notes actually fall.
A whole note followed by two half notes can stay quantized to a half-note grid, since every note lands on a valid division. Only shift to smaller values like quarter notes when notes are positioned off-grid.
After quantizing, MIDI notes often end up overlapping or leaving gaps. Pressing backslash removes overlaps, and shift-backslash closes gaps by extending each note to meet the next, a shortcut known as Force Legato, also accessible under Edit > Trim.
He also shows a quick velocity fix: holding option while adjusting one note's velocity sets all selected notes to match, useful for evening out an inconsistent bass performance.