I’ve gone on another microtonal trip lately, and have been working with ratios again. The thing about composing music with frequency ratios is that it places you in a brave new world where each interval is made up of TWO numbers instead of one (as in the traditional system, a fourth, third, fifth, etc). There are also all kinds of undiscovered tones and frequencies and relationships. There has to be a way to explore all this!
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picture of the GUI for the reaktor arpeggiator
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For those of you that aren’t hopeless music nerds like myself, a frequency ratio is just a relationship between frequencies. It is also the language of a tuning system called “just intonation.” A basic example: In the key of A, with the root frequency being 440 hertz, the A in the next higher octave is related to the original note a440 by a frequency ratio of 2/1, and is 880 hz. A major third is the ratio 5/4, or 550 hertz. Instead of the normal 12 steps per octave of Equal temperament, there is an infinite gradation of frequencies that you can manipulate to your heart’s content. Â
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With all that freedom comes massive confusion. I have been trying to come up with some systems for composing with these numbers. The first most obvious idea would be to just make a fixed scale, choose a few notes, and play with that. That is fun! But, it doesn’t take advantage of all the flexibility that working with just intonation truly gives you. Instead of just choosing 7 or 12 or 10 notes, you can start with a set of 5 notes, and make them mutate and evolve into an infinity of other frequencies, but all logically related by numerical relationships!
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This is my first system for making melodies and chords in just intonation: a harmonic arpeggiator. There are two different tables containing numbers for the numerator and denominator, and these tables can be moved through independently, at different speeds. Midi input triggers notes, but only the time and octave of the input notes is taken, and the rest is controlled by the ratio sequencers.
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I have implemented this system in both my Nord g2 modular and in Reaktor, so I can make them work together. Â
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Here is a simple melodic sort of track I did with the g2 patch:
Mp3 Audio of “Hydrogen”
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Here is the Reaktor patch:
Reaktor Harmonic Arpeggiator
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Here are a couple g2 patches:
G2 Harmonic Arpeggiator with Karpluss Synthesis
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I will be coming up with more stuff soon! I want to make some programs that allow you to dynamically change the scale as you play. Not sure how easy that will be to do in the g2, but I’ll definitely be able to do it in reaktor.
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