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metro

Trigger Metronome

Generate a metronomic signal to be used in any circumstance an isochronous trigger is needed.

Syntax

ktrig  metro  kfreq [, initphase]

Initialization

initphase - initial phase value (in the 0 to 1 range)

Performance

ktrig - output trigger signal

kfreq - frequency of trigger bangs in cps

metro is a simple opcode that outputs a sequence of isochronous bangs (that is 1 values) each 1/kfreq seconds. Trigger signals can be used in any circumstance, mainly to temporize realtime algorithmic compositional structures.

📝 Note

metro will produce a trigger signal of 1 when its phase is exactly 0 or 1. If you want to skip the initial trigger, use a very small value like 0.00000001.

Examples

Here is an example of the metro opcode. It uses the file metro.csd

Example of the metro opcode.
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<CsoundSynthesizer>
<CsOptions>
-odac -B441 -b441
</CsOptions>
<CsInstruments>

sr     =        44100
kr     =        100
ksmps  =        441
nchnls =        2

       instr    1
ktrig metro 0.2
printk2 ktrig
        endin

</CsInstruments>
<CsScore>
i 1 0 20


</CsScore>
</CsoundSynthesizer>

Here is another example of the metro opcode. It uses the file metro-2.csd

Another example of the metro opcode.
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<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
-odac   ;;;realtime audio out
;-iadc    ;;;uncomment -iadc if realtime audio input is needed too
; For Non-realtime ouput leave only the line below:
; -o metro-2.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>

sr = 44100
ksmps = 32
nchnls = 2
0dbfs  = 1

instr 1

kpch    random   1,20           ;produce values at k-rate
ktrig   metro    10             ;trigger 10 times per second
kval    samphold kpch, ktrig    ;change value whenever ktrig = 1 
asig    buzz     1, 220, kval, 1;harmonics
        outs     asig, asig

endin
</CsInstruments>
<CsScore>
f 1 0 4096 10 1 ; sine

i 1 0 10
e
</CsScore>
</CsoundSynthesizer>

See also

Sensing and Control: Tempo and Sequencing

More information on this opcode in the Floss Manuals: https://flossmanual.csound.com/csound-language/control-structures

Credits

Written by Gabriel Maldonado.

First Example written by Andrés Cabrera.

New in Csound 5 (Previously available only on CsoundAV)