turnoff — Enables an instrument to turn itself off.
turnoff -- this p-time statement enables an instrument to turn itself off. Whether of finite duration or “held”, the note currently being performed by this instrument is immediately removed from the active note list. No other notes are affected.
The following example uses the turnoff opcode. It will cause a note to terminate when a control signal passes a certain threshold (here the Nyquist frequency). It uses the file turnoff.csd.
Example 474. Example of the turnoff opcode.
See the sections Real-time Audio and Command Line Flags for more information on using command line flags.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform ; Audio out Audio in -odac -iadc ;;;RT audio I/O ; For Non-realtime ouput leave only the line below: ; -o turnoff.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> ; Initialize the global variables. sr = 44100 kr = 4410 ksmps = 10 nchnls = 1 ; Instrument #1. instr 1 k1 expon 440, p3/10,880 ; begin gliss and continue if k1 < sr/2 kgoto contin ; until Nyquist detected turnoff ; then quit contin: a1 oscil 10000, k1, 1 out a1 endin </CsInstruments> <CsScore> ; Table #1: an ordinary sine wave. f 1 0 32768 10 1 ; Play Instrument #1 for 4 seconds. i 1 0 4 e </CsScore> </CsoundSynthesizer>