40 lines
1.5 KiB
Markdown
40 lines
1.5 KiB
Markdown
# Bifurcator instrument editor
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Bifurcator instrument editor consists of these macros:
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- **Volume**: volume sequence.
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- **Arpeggio**: pitch sequence.
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- **Parametet**: set parameter of logistic map function.
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- **Panning (left)**: output level for left channel.
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- **Panning (right)**: output level for right channel.
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- **Pitch**: fine pitch.
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- **Load Value**: changes the current output value.
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## audio generation description
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Bifurcator uses logistic map iterations for sound generation.
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basically it runs the following function over and over:
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```
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r = (1 + (p / 65536)) * 2
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x = (r * x) * (1 - x)
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```
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where `x` is the current output value and `p` is the "parameter".
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by varying the parameter, the value of x may change drastically, producing a variety of sounds.
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the higher the parameter, the more "chaos" is present, effectively yielding noise.
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the default parameter is `47360`, which results in a square wave.
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if the parameter is set to 0, there's no sound at all.
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as the parameter approaches 32768, a decaying square wave is produced.
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the square wave stops decaying past 32768 and becomes louder until the parameter hits ~47496 (`r = 1 + sqrt(6)`).
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a second square wave one octave lower then starts appearing, until the parameter reaches ~51443 (`r ≈ 3.56995`). this is where chaos begins.
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anything higher results in a total mess.
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however, at ~59914 (`r = 1 + sqrt(8)`) you can hear a 33% pulse wave.
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## the importance of loading the value
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you must load a value that isn't 0 in order to get sound. otherwise the function will always output 0.
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