I received the score in 1961 and prepared for a month, practicing a page a day at most for an hour or so. I concentrated mostly on the position changes on the keyboard and at the same time memorized the score. Rhythmic notation in this case was an approximation of probabilistic density written in quintuplet versus sextuplet and this density was itself an approximation of the texture.
It is more important to make the texture felt than the note-to-note process as in melodic music. The whole of the selected pitches are like a pigment accumulation. There are two layers superimposed in fortissimo and pianissimo.
Here there is more diversified texture than in Herma. Scattered or converging clouds, pulsating rhythms abound. Chromatic sensation of each sound aggregate and the feeling of drive toward catastrophe pervades the work. Xenakis wanted the performers physically exhausted during the performance, feeling that something was still going on beyond fatigue.
3. Evryali and Synaphaï
Multilinear melodic synergy as Medusa's hair, Xenakis wanted each of ten fingers to move independently. But it is physically impossible and psychologically beyond control. I proposed instead of quickly shifting the focus from one layer to another. Xenakis wanted to know how I could create a rift between two consecutive touches instead of connecting. Together, we experimented and found that with minute interruption and delay with slight difference of touch one could create the impression that two consecutive pitches are not the part of a melody but separate individual tone-colors.
When I conducted this orchestral work, it was important not to divide the beat but realize an extremely slow beat of metronome 36. Then each player could fit in this time frame with layered quintuplets, sextuplets, etc. flattened out. The result is a dense wall of sound. There is a strange sense of remoteness, the feeling for the other side of this wall.: destiny's indicator.
Yuji Takahashi (2008)