1.Outline / 2.The Progression of the Story / 3.Stage(1) / 4.Stage(2) / 5.Stage(3) / 6.Stage(4) / 7.The Final Word&Credits
  PA System
  The PA system is a four channel speaker system built around a Yamaha O3D mixer board. The four speakers are not quadraphonic, they are placed in specific locations on the stage such as near the screen and where the vocalist is standing (please see the stage setup diagram). Natural balance and orientation is achieved using the volume of the vocalist's voice as
the standard.
All the sound inputs are sent to the YAMAHA O3D mixer and leave through the Bus out and Aux out as the operator carries out the appropriate routing and mixing according to each scene of the opera. The inputs include the microphone in the vocalist's hair, the sin waves produced by computer from the performance of the four keyboards, white noise, the output from the software sampler, narration prepared on CD-Rom and also the metronome click that is sent to the vocalist's headphones.

<Sound System Chart>

Sound System
  The sin wave sounds produced on stage by the keyboard players and computer algorithms, and the filtered white noise are the raw sound materials characteristic of this opera. The melody in the music score used for the keyboard performance is generated according to the same algorithms that are used for real time generation. These algorithms can be divided into two main groups, which have been called the algorithms used for speech synthesis and the algorithms used to generate 'God's Melody'.
There has already been an explanation of the algorithms for speech synthesis that realize formant synthesis through the performance of the keyboards, so there will be no further explanation here (please see reference materials: Literature: Word Shadows (Kotoba no kage) or Alleluia introduction).
The algorithms used to generate 'God's Melody' are extremely simply constructed algorithms that generate four 'voices' by picking musical notes according to random numbers. However, the special feature of the algorithms is their small range, in other words, they have been created so that the different 'voices' do not simultaneously choose the same note from the small number of notes available. Consequently the 'voices' may choose the same note consecutively, thus sounds are produced that have few changes, few developments but are continuously moving. 'God's Melody' is performed partly in Part 2, 2a with sin waves generated from the performance of the keyboards, in Part 3, 3a with the keyboards and the sampled voice of the vocalist, and in sections 3b and 3c with the automatic performance generated in real-time by sin waves.