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Problems with subst-rhythm

I have tried to do the examples from Mikhail Malts Text “Some considerations on Brian Ferneyhough’s Musical Language - Part 1” from the “The OM Composer’s Book 2”, which is helpful for my Phd Thesis about Syntax and algorithmic Composition. I have a problem with the generic function “subst-rhythm”. Whenever I try to connect the subst-rhythm Object with the Voice Object, it gives me different results, than in the book. Can you find the mistake? The mistake is in the two voice Objects below. It would be helpful, if you have the book to compare with the screenshots in the book.


It would be helpfull if you send the patch.That way it will save me some time.


See attached



03022019b-2.omp (33.6 KB)

This is the example from the book (see also attached).


Ok thanx Caspar.

Some explanations:

Well the problem here is with the author’s examples and the version of subt-rhythm used in. The author being Mikhail, who was at the origin of this function which was done in PatchWork, the ancestor of OM. So i believe he copied (or exported the example as is) from Patchwork. I re-wrote the code sometime now, in order to make the function more universal, using either proportions or list of proportions.
So the first change is in the positions. In Lisp and many other computer languages, the positions start with 0. I know it is not that intuitive for a musician, So what you should do, is just decrement the position (substracting fron the list of position -1).
Second, if you have just atoms, like int his example, the om version of subt-rhythm will just substitute the proportion and NOT subduvude the existant proportion. So In the attachment you will find, you will see a loop. this will create for all positive integers a list, so it will get subsitutted in the existant proportions (cf. help of the subst). So for instance the first subdivision, here 5 will be transformed into (1 1 1 1 1) , etc… And if you notice, the -6, it’s maybe a Ferneyhough convention in his example is not a proportion, but just turns the given note position into a rest.

Hope this helps.


03022019b-3.omp (40.6 KB)

Great! Thanks!

Hello Casparo and Karim, I haven’t found tutorial patches for OM-Combine “The Ferneyhuough library”. Do you know if it exists a PDF with examples? I think some of the technics can be useful in my work.

Best, Dagfinn

Dear Dagfinn,

Soryy for the very very late reply, But most of these post are not reported to me, since i didn’t figure out how to fix the preferences in this funny interface.

So in order to answer you, unfortunately no. There’s no tutorial or documentation for this library. I would also like to have one myself by the way. However one good and great tutorial should be the article mentioned above :slight_smile: Mikhail Malts Text “Some considerations on Brian Ferneyhough’s Musical Language - Part 1” from the “The OM Composer’s Book 2”.