TOOT 5

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To add some delayed vibrato to our chorusing instrument we use another oscillator for the vibrato and a line segment generator, linseg, as a means of controlling the delay. linseg is a k-rate or a-rate signal generator which traces a series of straight line segments between any number of specified points. The Csound manual describes it as:

kr linseg ia, idur1, ib[, idur2, ic[...]]
ar linseg ia, idur1, ib[, idur2, ic[...]]

Since we intend to use this to slowly scale the amount of signal coming from our vibrato oscillator, we'll choose the k-rate version. The i-rate variables: ia, ib, ic, etc., are the values for the points. The i-rate variables: idur1, idur2, idur3, etc., set the duration, in seconds, between segments.

orchestra

 File: Toot05.orc
 instr 5

irel      =         0.01                               ; set vibrato release time

idel1     =         p3 * p10                           ; calculate initial delay (% of dur)

isus      =         p3 - (idel1 + irel)                ; calculate remaining duration



iamp      =         ampdb(p4)

iscale    =         iamp * .333                        ; p4=amp

inote     =         cpspch(p5)                         ; p5=freq



k3        linseg    0, idel1, p9, isus, p9, irel, 0    ; p6=attack time

k2        oscil     k3, p8, 1                          ; p7=release time

k1        linen     iscale, p6, p3, p7                 ; p8=vib rate



a3        oscil     k1, inote*.995+k2, 1               ; p9=vib depth

a2        oscil     k1, inote*1.005+k2, 1              ; p10=vib delay (0-1)

a1        oscil     k1, inote+k2, 1



          out       a1+a2+a3

          endin

score

 File: Toot05.sco
f1   0    4096 10 1      ; sine wave



;ins strt dur  amp  freq      atk  rel  vibrt     vbdpt     vbdel

i5   0    3    86   10.00     0.1  0.7  7         6         .4

i5   4    3    86   10.02     1    0.2  6         6         .4

i5   8    4    86   10.04     2    1    5         6         .4

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