--+--root
  |
  +--+--Master--(QString Key)
  |  +-----("Title",   String)
  |  +-----("Author",  String)
  |  +-----("Version", String)
  |
  +--+--Mixer--(QString Key)
  |  +-----(int FederId, int Volume, int Panpot)
  |  +-----(int FederId, int Volume, int Panpot)
  |  +...
  |
  +-----ControlItem--("Tempo")--Data--(int tick, double value)--(int tick, double value)--...
  |
  +-----ControlItem--("Measure")--Data--(int tick, int val1, int val2)--(int tick, int val1, int val2)--...
  |
  +--+--TrackItem--("Track1")
  |  +--+--Events
  |  |  +--Data--(int tick, int length, unsigned char note)
  |  |  +--Data--(int tick, int length, unsigned char note)
  |  |  +--Data--(int tick, int length, unsigned char note)
  |  |  +--Data--(int tick, int length, unsigned char note)
  |  |
  |  +--+--SequenceItem(ViewType, Editable, TimeType, FramePeriod)
  |  |  +-----ControlItem({tick, value}, {tick, value}, ....)
  |  |
  |  +...
  |
  +...

 
