\score {
  \header {
    title = "Das Lieben bringt groß Freud"
  }
  \new ChoirStaff <<
    \new Staff <<
      \set Score.skipBars = ##t
      \new Voice = frauen { \global \oneVoice \frauenPausen }
      \new Voice = sopran { \global \voiceOne \sopranMelodie }
      \new Voice = alt    { \global \voiceTwo \altMelodie }
    >>
    ifdef(`STR_1',`\new Lyrics \lyricsto alt { \textI }')
    ifdef(`STR_2',`\new Lyrics \lyricsto alt { \textII }')
    ifdef(`STR_3',`\new Lyrics \lyricsto alt { \textIII }')
    \new Staff <<
      \new Voice = maenner { \global \clef "bass" \oneVoice \maennerPausen }
      \new Voice = tenor   { \global \clef "bass" \voiceOne \tenorMelodie }
      \new Voice = bass    { \global \clef "bass" \voiceTwo \bassMelodie }
    >>
    ifdef(`STR_1',`\new Lyrics \lyricsto bass { \bassTextI }')
    ifdef(`STR_2',`\new Lyrics \lyricsto bass { \bassTextII }')
    ifdef(`STR_3',`\new Lyrics \lyricsto bass { \bassTextIII }')
  >>
  \layout {
    indent = #0
  }
}