Orchestra with many instruments
Tutorial MyClass_03 Orchestra with many instruments
instr 1 | Starts the instrument #1 block. |
gifreq = p4 | The frequency as global variable is set to p4 |
endin | Ends the current instrument block |
instr 2 | Starts the instrument #2 block. |
idur = p3 | The duration is set to p3 |
idurosc = 1/idur | The duration of the amplitude envelope is set to 1/idur |
iamp = (p4 > 0.0 ? (p4*0.001*0dbfs) : (ampdbfs (p4))) | The variable p4 sets the amplitude. Linear values from 0 to 1000 or in dB from 0 to negative values |
iaenv = p5 | Function table number of the wave form of the amplitude envelope (GEN routine) |
iport = p6 | The frequency portamento is set to p6 |
initfreq = p7 | The starting frequency of the portamento is set to p7 |
kfreq = gifreq | The local frequency is set equal to the global frequency |
kfrqp portk kfreq,iport ,initfreq | The portamento of the frequency is made by a step-valued control signal. |
aenv poscil iamp, idurosc, iaenv | Amplitude envelope |
asig poscil aenv,kfrqp,1 | The opcode "poscil" generates an audio signal with the waveform of the GEN subroutine #1 and aenv as amplitude envelope, then writes the output to the audio variable "asig" |
out asig | The opcode "out" writes the audio data to an external device or stream. |
endin | Ends the current instrument block |
This orchestra is a oscillator with the following controls
- The frequency of the oscillator,
- The waveform of the oscillator,
- The envelope amplitude of the global audio file,
- The portamento time of each frequency.
Make your OMChroma class
Copy the complete following instructions in a text file and save it as"myclass3.orc".
sr = 96000
kr = 96000
ksmps = 1
nchnls = 1
0dbfs = 8388607
instr 1
gifreq = p4
endin
instr 2
idur = p3
idurosc = 1/idur
iamp = (p4 > 0.0 ? (p4*0.001*0dbfs) : (ampdbfs (p4)))
iaenv = p5
iport = p6
initfreq = p7
kfreq = gifreq
kfrqp portk kfreq,iport ,initfreq
aenv poscil iamp, idurosc, iaenv
asig poscil aenv,kfrqp,1
out asig
endin
Make a new class following the steps of the Tutorial MyClass_01 Three lines class and Tutorial MyClass_02 Initialize GEN slots. After the valuating of the get-instrument two warning windows will pop up, each of them with the name of the instrument defined. |  |
 | Clearly in the "Classes in package Chroma User" folder you will find two new instruments : myclass3-1 and myclass3-2 |
 | Remember to initialize the aenv slot (p5) with a Csound table (see Tutorial MyClass_02 Initialize GEN slots) |
In this example you can see how two Csound instruments work together. The frequency's data will pass via the global variable inside Csound from the first instrument, which reads the score note by note but doesn't make any sound synthesis, to the second which changes the frequency of the oscillator at every new incoming note and renders the audio file.
