rostasi

"Le Sacrifice" is the second part of a triptych of pieces he wrote ("Anastenaria").
That piece is really on the cusp of his change to the modernist nature of the works
that follow with its modal serialism derived from Messiaen. You can hear how he took
eight fixed pitches and assigned Fibonacci-based durations along with the glissandi
that is so familiar to his works thereafter. Also, you might notice the lack of vibrato.

His first explicit use of mathematics (also with the Fibonacci sequence)
occurred back in '52 with "Tripli Zyia" while, before then, his interest
would lie more in the sonorities of Ravel and Bartók ("Phipli Zyia").
As a matter of fact, he had said that he wanted to be the "Greek Bartók").