+voiceOneStyle = {
+ \override NoteHead #'style = #'diamond
+ \override NoteHead #'color = #red
+ \override Stem #'color = #red
+ \override Beam #'color = #red
+}
+voiceTwoStyle = {
+ \override NoteHead #'style = #'triangle
+ \override NoteHead #'color = #blue
+ \override Stem #'color = #blue
+ \override Beam #'color = #blue
+}
+voiceThreeStyle = {
+ \override NoteHead #'style = #'xcircle
+ \override NoteHead #'color = #green
+ \override Stem #'color = #green
+ \override Beam #'color = #green
+}
+voiceFourStyle = {
+ \override NoteHead #'style = #'cross
+ \override NoteHead #'color = #magenta
+ \override Stem #'color = #magenta
+ \override Beam #'color = #magenta
+}
+voiceNeutralStyle = {
+ \revert NoteHead #'style
+ \revert NoteHead #'color
+ \revert Stem #'color
+ \revert Beam #'color
+}
+