Fmelodies I (1983-84), for chamber ensemble and computer sounds

The application of techniques of frequence modulation (FM), very widespread in the analogue synthesizers, has opened new possibilities with the use of computer technology. Computers allows a conscious and precise generation and manipulation of FM spectrums.

FM synthesis allows to generate spectrums with different groups ot the harmonic series. The harmonic content of the resultant spectrum (its relative “harmonicity” or "un-harmonicity") is determined by the numeric relation of the Carrier Frequency (CarF) to the Modulating Frequencies (MoF). If these frequencies constitute a “simple” ratio (represented with low numbers, e.g. 1:1, 2:3, 5:3) the resultant spectrum has an "harmonic", "consonant" quality. If the ratio is represented with higher numbers (15:7, 36:1, 128:13) the spectrum becomes increasingly "non-harmonic", "dissonant".

In "Fmelodies I" two frequencies are used as a carrier: 69.3 cps. and its 17th partial 1178.1 cps. These notes become thus referential notes of the composition, the first of them (69.3 cps., C sharp) somewhat like a "tonica" of the whole composition.

The generated spectrae are used in two ways:

- "Melodies" with the notes of the spectrae are created with digital filters and then recorded on tape;

- This notes determines as well the melodic and harmonic material of the instrumental part part of the soloist.

In a first version of Fmelodies, the recorded computer sounds were contrasted with the sounds of a chamber orchestra. In Fmelodies II, for Cello Solo and Percussion, I strived for transparency in chamber-music like textures between instrumental and synthetical parts.

Commision: Ircam, Paris

Ed. Salabert