# Harmonic Skinns

Salute! Years ago I programmed Rolf Wallin’s Crystal Chord algorithm in Open Music. It isn’t the most elegant programming I have made, but I learned a lot. Ruben has made a much better one, and also included it into his great library OMRuben.

I have used CAC since the days of PatchWork mostly for pitch. My knowledge of maths isn’t the best, so a lot of the solutions I have chosen could have been better. I am no diving into OM-loops.

Best, Dagfinn

Hud-harmonic-skinn.zip (4.06 MB)

Dagfinn,

I just had a chance to read your article on Wallin’s Crystal Chords posted on Academia: https://www.academia.edu/33501437/Rolf_Wallin_Crystal_Chords I found it to be very informative!

Would you be willing to share your OM Crystal Chords patch by posting it on the forum?

Out of curiosity, looking at the second step in the process [Germ Interval 2]: is there a reason why the system requires to stack the Germ interval “twice”: first on each resulting pitch generated in the first step [Germ Interval 1], and then on each of those resulting pitches? Is this index arbitrary?

Germ Int 1: A#, A, G#, G
Germ Int 2 (first stacking): A=>C, G=>B, G=>A#
Germ Int 2 (second stacking): C=>D#, B=>D, A#=>C#

Many thanks!

Zvony

Hello Zvony, thanks for reaching out. I think Rolf has made it this way, to get intervals close to each other. If you download the OMRuben library Ruben Sverre Gjertsen has made a much more elegant solution using OM Loop after I presented mine for him. I will post another way to do this in the sam thread.

Best, Dagfinn

rolf_wallin_crystal_chord.omp (18.8 KB)
crystalchord.omp (64.4 KB)

Hello again Zvony, I have made a slightly different version where I have a scale which is applied on a transposition row. I got help with the patch from Fabio De Sanctis De Benedictis. Just for the fun of it, have I added my first attempt. D.Koch Scal builder OLD VERSION.omp (25.9 KB)

Best, Dagfinn

D.KOch Harmonic Skin.omp (25.3 KB)
Dagfinn Koch - Harmonic Skins.pdf (1.2 MB)

Dagfinn,
Thanks for following up. I appreciate you sharing the patches and suggestions. I look forward to trying them out; will share comments if there’re any.

All the best wishes,
Zvony

Dagfinn,
Sorry for double-posting. I just had a chance to look at your extended work that you referenced in the last post. Very impressive! I wonder if there may be a resource one could study or read more about your extension of Wallin’s Crystal Chords, especially in the context of the processes used by Fabio De Sanctis? Mainly for educational purposes.

Thank you once again,
Zvony

Zvony, here an article by Rolf explaining the crystal chord idea. For fun, I call it his Crystal Meth(od). I’ve also added an older version of my harmonic skin algorithm. Rolf has also given me a MAX-patch developed at IRCAM. He doesn’t use Open Music himself.

In the added score, I use harmonic skins. <a class=“attachment” href="/uploads/KOCH - PALIMPSEST - SCORE.pdf (143.4 KB)
default/original/2X/c/ca69774648247bf9c91c1747b34497c644c215bc.pdf">Zugabe-analyse.pdf (1.8 MB)

I’m developing some other patches where I use “posn-match” extensively which I think can be interesting for you. It is about transformations between skins and block voicing using permutations.

Best, Dagfinn

Crystalarticle01.pdf (904.2 KB)
Guitar_Harmonic_Skinn_Algotithm.pdf (177.3 KB)

Dagfinn,
Thanks so much for sending more information! Yes, I find it all very interesting and can’t wait to learn more. Thank you once again!
Zvony