Description

midiarp constructs arpeggios based currently held MIDI notes. The opcode will output notes in the form of MIDI note numbers, and a metronomic signal that can be used to sequence the notes. Users can choose the rate at which the notes are generated, and may also choose from a set of arpeggio patterns.

Syntax

kMidiNoteNum, kTrigger midiarp kRate[, kMode]

Performance

kRate -- sets the rate in cycles per second at which new notes will be generated.

kMode -- Optional. Sets the mode of the arpeggio. 0 for up and down, 1, for up, 2 for down, and 3 for random. If left out, it will default to mode 0, up and down.

kMideNoteNum -- the current note number in the arpeggio pattern.

kTrigger -- a metronomic pulse that can be used to trigger playback of the notes in the arpeggio. This signal will output a 1 followed by 0s on each cycle. The frequency is set using the kRate input parameter.

Example

This example shows how midiarp can be used to trigger arpeggios using a secondary instrument for playback. Instrument 100 listens to incoming MIDI notes, and then triggers playback using instrument 200. massign is used to prevent instrument 100 from being triggered each time a new MIDI note is pressed. This examples uses the file midiarp.csd.

<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
; Audio out   Audio in    No messages
-odac 	-d    -m0d --midi-key-cps=4 --midi-velocity-amp=5  -F midiChords.mid
; For Non-realtime ouput leave only the line below:
; -o midiin.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>
; Initialize the global variables. 
sr = 44100
ksmps = 32
nchnls = 2
0dbfs  = 1

massign 1, -1; prevent triggering of instrument with MIDI

instr 200

    kMode = 0
    kTempo = 8
    kNote, kTrigger midiarp kTempo
    kFilterFreq lfo 2000, .05, 1

    ;if kTrigger is 1 trigger instrument 300 to play
    if kTrigger==1 then 	
        event "i", 300, 0, .5, .5, kNote, abs(kFilterFreq)+200
    endif

endin

instr 300

    kEnv expon p4, p3, .001
    aOut vco2 kEnv, cpsmidinn(p5)		;convert note number to cps
    aFilter moogladder aOut, p6, .2
    outs aFilter, aFilter
    
endin

</CsInstruments>
<CsScore>
i200 0 60
</CsScore>
</CsoundSynthesizer>

Credits