\version "2.19.37"
\layout {
  \context {
    \Score
    \remove Timing_translator
  }
  \context {
    \Staff
    \consists Timing_translator
  }
}
<<
  \new Staff {
    \time 9/8
    s4.*6
  }
  \new Staff {
    \time 9/8
    4. 4. 4.
    \set Staff.timeSignatureFraction = 3/4
    \scaleDurations 3/2 { 4 4 4 }
  }
>>