Phrase level controls

1
Phrase level controls

• Making legato lines in Csound

2
Legato lines

• Legato To play or sing groups of notes smoothly
  and without separate attacks
• Two methods
• Piano style notes slightly overlap
• i01 0 1.2 durations are longer than
• i01 1 . the intervals between
• i01 2 . successive notes
• Vocal style notes connected smoothly
• Successive notes are sung or played in the same
  breath
• New notes are not accented or re-articulated

3
Legato lines in Csound

• Use a p-field other than p3 for your envelope
  duration
• The first i-statement sets the envelope duration
  for the entire phrase
• Subsequent i-statements use -1 for the envelope
  duration and oscil phase
• Csound envelope units will skip initialization if
  the duration argument is negative
• Csound oscil units will skip initialization if
  the phase argument is negative

4
Vocal style legato example
Orchestra excerpt
idur (p6 0 ? p3 p6) default to
p3 iphs (idur lt 0 ? -1 0) set oscil phase
kenv linen iamp, irise, idur, idecay if idur lt
0, no init asig oscili kenv, icps, ifn, iphs if
iphs lt 0, no init
Score excerpt
nn st dur amp pch envdur i01 0 .5 10000 8.00 2 s
tart phrase i01 . . 8.02 -1 dont
initialize i01 . . 8.04 i01 . . 8.05
5
Adding portamento

• In some cases, you will hear clicks at the
  beginnings of new notes in a phrase
• Caused by oscils instantaneous change in pitch
• Fix by using a short portamento (gliss) from
  previous to next pitch in the melody
• Best implemented using octave format and a linseg
  unit.
• With linseg, remember to level off!
• Use the pp score operator to obtain the pitch
  from the previous instrument statement

6
Portamento example

• Orchestra excerpt
• inew octpch(p5)
• iold (p7 0 ? inew octpch(p7))
• koct linseg iold, .01, inew, 1, inew level
  off after gliss
• asig oscili iamp, cpsoct(koct), ifn, iphs
• Score excerpt
• nn st dur amp pch envdur prevpch
• i01 0 .5 10000 8.00 2 0
• i01 . . 8.02 -1 pp5
• i01 . . 8.04

7
In class designs

• Modify Sample Orc2 to support legato
• Make a global crescendo instrument
• Make an instrument that uses starting time to
  determine stereo pan position