This run unites two instruments like siamese twins.
Instrument 1 basically consists of a carrier (3 or 6 harmonics), an envelope and a LFO modulation of amplitude, imparting some vibrato effect. The effect of the RANDI unit is negligible.
Instrument 2 (see right figure) produces a slightly amplitude modulated sinus tone, whose frequency is controlled by two linear functions. One of these functions does nothing (!). This in contrast to f9, which brings in a frequency rise of 10%, from 90% to 100% of the specified frequency (which is really the amplitude input of the oscillator).
The function of instrument 2 is partly to emulate the attack portion of a flute tone and partly to enrich the timbre of the complete tone (when playing parallel to instrument 1).
For an acoustic impression of the complexity of this design, one should listen to the two instruments apart. The score files 80_01_2B.SCO and 80_01_2C.SCO are included in the catalogue to this end. (Risset 1969: #100; Vercoe 1993: morefiles/risset1.orc)
Orchestra and Score
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