On Wed, Apr 20, 2022 at 08:54:21PM +0300, Omer Katzir wrote: > Unfortunately it doesn’t solved, because I want to add a complete new > part and not move one voice.
Oh I see. In that case, what you want is something like this: \score { << \new GrandStaff << \new Staff = "guitar traditional" << \clef "treble_8" \context Voice = "upper" \upper \context Voice = "lower" \lower >> \new TabStaff << ... % what you had before >> >> \new PianoStaff << \new Staff = "piano righthand" << \clef treble ... % piano notes here >> \new Staff = "piano lefthand" << \clef bass ... % piano notes here >> >> >> } T -- Gone Chopin. Bach in a minuet.