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Tutorial 15 not working as expected

Hi! I am working through the IRCAM tutorials and I cam across a weird problem with tutorial 15. When I evaluate the Chord-Seq box I got an output that I was not expecting. I was expecting all notes above middle C (6000 midicent) to be in channel 1 and all notes below in channel 2. But there were notes assigned to channel 1 well below 6000 and some notes above this assigned to channel 2. Now I tried feeding both the chord-seq and om-loop box with a list of midicents and it all worked perfectly. But if I switched back to using the random patch it went wrong again.
Now I did check the output of the random patch by copying the list it produced into a text editor and it all looked fine.
Why would it work with a fixed list and not with a randomly generated list.
I have screen shots but I don’t know it I can attach them to this message.
This all is very puzzeling.
Anyone any idea why this is happening?

Hi fm42

I suspect that you have unset the “note generator” patch in mode once. To do so:
-Select the patch “note generator”
-press ‘b’
-then click on the upper left corner cross of the icon once.
-it should turn into a 1 meaning evaluate once
THe reason of all this, is exaclty the random function inside this patch which is evaluate twice (one connected to the chord-seq object, the other one to the loop. So you will have random numbers evaluated twice, which will not meet the omif test of loop exaclty with the first output connected to the chord-seq objet, meaning that they are different numbers…
Read more on this here:
http://recherche.ircam.fr/equipes/repmus/OpenMusic/user-doc/DocFiles/Tutorial/tut015/Index.html

Best
K

That’s it! Thank you