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Scale Chords (Harmonies)

OpenMusic
#1

I’m working on a simple educational example for which I’d like to create a patch that constructs a series of chords (harmonies) on the melodic degrees of a given scale. For instance, a very simple example is a C major scale that produces a series of triads in root position that, where each triad is built on each successive scale degree. The result is a series of parallel chords that keep the spacing of the given chord (e.g. root position triad) while adhering to the intervals distribution inherent in the given scale (voice-leading).

In the attached patch, it is the chord-seq that features the result I wish to achieve. Perhaps there’s an existing OM library or patch that would be useful in this situation? I welcome your suggestions.

Thank you very much for your help!

scale-chords.omp (7.92 KB)

#2

Hello — I don’t know if that can help, but OM includes a few hidden/undocumented ‘tonal’ functionalities which might help working with major/minor scales etc.
First, you can assign a tonality attribute to an object (typically, a chord) using the t key in the score editor.

When the object has a tonality, it can be transposed through functions such as transpose-tonal (transposes to a number of degrees, depending on the origional tonality), transpose-modulant (transposes to another tonality), etc.

#3

Thanks, Jean. I’ll definitely look into assigning tonality attributes to an object as you suggested. If it’s not too much trouble, could you define the outputs found at the transpose-tonal function?

In my project, I would like to go beyond major/minor scales, thus being able to apply this process of derivation of chords to any ordered pitch collection. Perhaps I may need to define custom tonality, or “pitch space” that could then be transposed to the selected scale degrees found in the starting chord?

Thank you once again!

#4
could you define the outputs found at the transpose-tonal function?

— what do you mean ?

In principe the output is just a new chord (or object of the same kind as the input), transposed.

#5

My apology, I meant to define the two INPUTS. I understand that the first one is the chord under consideration. Would the second one be assigned to a scale? Or is the second input intended for custom values of a sort?

Thank you once again!

#6

… well, I guess it’s just a number of degrees (integer)