improvisationOn = {
\set squashedPosition = #0
\override NoteHead.style = #'slash
+ \override TabNoteHead.style = #'slash
\override Accidental.stencil = ##f
\override AccidentalCautionary.stencil = ##f
}
improvisationOff = {
\unset squashedPosition
\revert NoteHead.style
+ \revert TabNoteHead.style
\revert Accidental.stencil
\revert AccidentalCautionary.stencil
}