\version "2.4.6"

\paper {
  #(set-paper-size "a5")
  linewidth = 60\staffspace
  bottommargin = 9\mm
  aftertitlespace = 6.0 \mm
  indent = 0\mm
}

top = {
  \clef G
  \set Staff.verticalExtent = #'(-0.0 . 5.5)
  \time 6/8
  \override Staff.Hairpin #'height = #'0.5
  #(set-accidental-style 'modern-voice)

  \partial 8 r16
  << { \tieNeutral <as' ges''>16 ~ | 
    <as' ges''>4 <d' c''>16 <d' c''> <f' a'> <f' a'> c' <c' d> ~ <c' d> <c' d> ~ | } 
  \\ { s16 \ff | <as' ges''>8. 
    \change Staff = lower \stemUp es'16 
    \change Staff = upper \stemDown d' 
    \change Staff = lower \stemUp ges
    \change Staff = upper \stemDown f' 
    \change Staff = lower \stemUp bes, 
    \change Staff = upper \stemDown d s8. |  } >>
}

bottom = {
  \clef F
  \set Staff.verticalExtent = #'(-10.0 . 0.0)
  \time 6/8
  \override Staff.Hairpin #'height = #'0.5
  #(set-accidental-style 'modern-voice)

  \partial 8 <a f'>8 | 
  \clef G <g' des''>8) \sf 
  r16 <es'' ces''> \ff <es'' ces''> <as ges'> <as ges'> 
  \clef F <e bes> <e bes>8. <es ces'>16 | 
}

\score {
  \header {
    piece = "Präludium"
  }
   \context PianoStaff <<
      \set Staff.minimumVerticalExtent = #'(-10 . 10)
      \context Staff = upper \transpose c c' { \top }
      \context Staff = lower \transpose c c { \bottom }
   >>
   \layout {
      \context { \RemoveEmptyStaffContext }
      \context { \Staff \remove Key_engraver }
   }
}