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Synthesize OM Spectral Chord with CSound?


I have been having problem to synthesize chord derived from spectral analysis. I’ve looked at tutorials but I still couldn’t make any sound from csound-synth. Attached is the patch I made

It keeps showing a straight line in the sound file… I would appreciate any help for this.

Thank you in advance

The problem apparently is that you are missing an orchestra (orc) and you didn’t define one.
As i can see from your screenshot (not patch), you don’t have even an oscillator.
what kind of synthesis you need ? (i guess a simple additive ?)


Yes, I’m trying to make a simple additive…

Isn’t the orc file defined by the textfile connected to write-csound-orc? Also, how should I put the oscillator?

Sorry if my questions are really basic, I’m still trying to figure out all this synthesizing thing in OM…

Thank you so much,


In fact,there’s no textfile connected to write-csound-orc, In your screenshot, write-csound-orc will write just the header.
If you send in the patch, i can fix it if you want.


Here’s a drive link for the patch https://drive.google.com/file/d/16_vCrCJTzWX4iQ_KAUJTVmPsDqvT4VFW/view?usp=sharing

(I couldn’t attach it here since I’m a new user)

Thanks a lot!


Dear Natrj

Ok, first of all, the problem as stated before, is that you didn’t have any orc in the patch.
Second, you should always “write” a .sco according to a specific .orc, and vice-versa. So be really careful with your parameters, etc…
Now, you don’t have to “create” graphically an orchestra. It is much more practical in fact to type it.
So in this patch,

you can either use the “graphical” orchestra, or better connect the “text” orchestra to the second input of csound-synth.
Here is the attached patch:
Patchsynth.omp (22.7 KB)
You might encounter other problems, so don’t hesitate to submit them here.

Thank you so much!!!