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Filter certain notes in a chord

OpenMusic
#1

Hello everyone! I have two fundamental questions regarding note filtering in chords.

  1. Is it possible to filter specific notes within a chord? For instance, if I generate a harmonic series based on E1, how can I filter only the ‘E, F-sharp, A’ notes without changing the octave?

  2. How can I extract all chord permutations based on a predefined pitch-set? For example, using a harmonic series based on E1, I’d like to obtain all permutations of the pitch-set [0,2,6]. Ideally, the results should be displayed in their original positions within the chord.

Thank you very much!

#2

Hi wuiy97,

Here is a possible solution for filtering:

Screenshot_2024-01-31_13-36-05
Screenshot_2024-01-31_13-36-051216×842 50.9 KB

The patch:
filter-spectra.omp (14.5 KB)

However, this will output approximated values.

For your second question, please can you send an example?

BEst
K

#3

Hi Karim,

Thank you very much for your help with my first question; it was exactly what I needed.

For the second question, for example, a chord is (C4, E4, F#4, B4, C5, D5), then I want get all the possibilities of pitch-set [0,2,6], so the result would be ((C4, E4, F#4) (C4, F#4, D5) (E4, F#4, C#5) (F#4, C5, D5) …). Anyway all the permutations of [0,2,6].

Thank you very much!

Best wishes,

Yihao

#4

Can you first send me patch? I am not sure of your question regarding the pc set and your chord

#5

Thank you very much Karim! This is the patch, but I don’t know how to with it,
Patch 3.omp (4.5 KB)

#6

Hi,

You could compute all the [0, 2, 6] chords for each pitch of the original chord in a loop, and then reduce it to those that are included in the original chord (check included? OM function.)

All the best,
António

#7

By pc-set here you just mean all three note chords that have the same interval as [0 2 6] no (even if they are in different octaves)?

Because your first example i think was not correct:
(C4, E4, F#4, B4, C5, D5), then I want get all the possibilities of pitch-set [0,2,6], so the result would be ((C4, E4, F#4)

this one is not correct should be (c d f#) no?

#8

“By pc-set here you just mean all three note chords that have the same interval as [0 2 6] no (even if they are in different octaves)?” - Yes.

So for the (C4, E4, #F4) is the same as (#F4, E4, C4) [6,4,0] also is the [0,2,6] I think. There are so many permutations. That’s why I want to use computers to help with this.

#9

Hi Antonio Florenca,

Thank you very much. I will try it.

Best wishes,

Yihao