TOOT 12

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This is by far our most complex instrument. In it we have designed the ability to store pitches in a table, and then index them in three different ways: 1) directly, 2) via an lfo, and 3) randomly. As a means of switching between these three methods, we will use Csound's program control statements and logical and conditional operations.

orchestra

 File: Toot12.orc
instr 12

          iseed     =         p8

          iamp      =         ampdb(p4)

          kdirect   =         p5

          imeth     =         p6

          ilforate  =         p7                            ; rate for lfo and random index

          itab      =         2

          itabsize  =         8



if (imeth == 1)     igoto     direct

if (imeth == 2)     kgoto     lfo

if (imeth == 3)     kgoto     random



direct:   kpitch    table     kdirect, itab                 ; index f2 via p5

                    kgoto     contin



lfo:      kindex    phasor    ilforate

          kpitch    table     kindex * itabsize, itab

                    kgoto     contin



random:   kindex    randh     int(7), ilforate, iseed

          kpitch    table     abs(kindex), itab



contin:   kamp      linseg    0, p3 * .1, iamp, p3 * .9, 0  ; amp envelope

          asig      oscil     kamp, cpspch(kpitch), 1       ; audio oscillator

                    out       asig

                    endin

score

 File: Toot13.sco
f1   0    4096 10 1                                         ; Sine

f2   0    8    -2 8.00 8.02 8.04 8.05 8.07 8.09 8.11 9.00   ; cpspch C major scale



; method 1 - direct index of table values

; ins     strt dur  amp  index     method    lforate   rndseed

  i12     0    .5   86   7         1         0         0

  i12     .5   .5   86   6         1         0

  i12     1    .5   86   5         1         0

  i12     1.5  .5   86   4         1         0

  i12     2    .5   86   3         1         0

  i12     2.5  .5   86   2         1         0

  i12     3    .5   86   1         1         0

  i12     3.5  .5   86   0         1         0

  i12     4    .5   86   0         1         0

  i12     4.5  .5   86   2         1         0

  i12     5    .5   86   4         1         0

  i12     5.5  2.5  86   7         1         0

  f0      10

s

; method 2 - lfo index of table values

; ins     strt dur  amp  index     method    lforate   rndseed

  i12     0    2    86   0         2         1         0

  i12     3    2    86   0         2         2

  i12     6    2    86   0         2         4

  i12     9    2    86   0         2         8

  i12     12   2    86   0         2         16

  f0      16

s

; method 3 - random index of table values

; ins     strt dur  amp  index     method    lforate   rndseed

  i12     0    2    86   0         3         2         .1

  i12     3    2    86   0         3         3         .2

  i12     6    2    86   0         3         4         .3

  i12     9    2    86   0         3         7         .4

  i12     12   2    86   0         3         11        .5

  i12     15   2    86   0         3         18        .6

  i12     18   2    86   0         3         29        .7

  i12     21   2    86   0         3         47        .8

  i12     24   2    86   0         3         76        .9

  i12     27   2    86   0         3         123       .9

  i12     30   5    86   0         3         199       .

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