TOOT 2

The first instrument was not interesting because it could play only one note at one amplitude level. We can make things more interesting by allowing the pitch and amplitude to be defined by parameters in the score. Each column in the score constitutes a parameter field, numbered from the left. The first three parameter fields of the i statement have a reserved function:

p1 = instrument number

p2 = start time

p3 = duration

All other parameter fields are determined by the way the sound designer defines his instrument. In the instrument below, the oscillator's amplitude argument is replaced by p4 and the frequency argument by p5. Now we can change these values at i-time, i.e. with each note in the score. The orchestra and score files now look like:

orchestra

File: Toot02.orc

instr 2 a1 oscil p4, p5, 1  ; p4=amp out a1  ; p5=freq endin

score

File: Toot02.sco

f1 0 4096 10 1  ; sine wave ;ins strt dur amp(p4) freq(p5) i2 0 1 2000 880 i2 1.5 1 4000 440 i2 3 1 8000 220 i2 4.5 1 16000 110 i2 6 1 32000 55 e