Tone Generation - Noise Engineering Cursus Iteritas Manual

Noise Engineering
Cursus Iteritas
Dynamically generated wavetable oscillator using orthogonal functions.

Tone Generation

Cursus Iteritas generates a spectral description based on knob positions. Center, Width, Tilt, Structure
determine amplitudes for each harmonic. This description is fed into the inverse transform for the
current function set to produce the time-domain wavetable. The wavetable is normalized to reduce
amplitude variations across spectral changes.
Oversampling of the wavetable depends on pitch: lower octaves have higher oversampling since the
sample rate only varies by a factor of two. The Edge control interpolates the oversampling from point
sampling to a cubic-spline interpolation (NURBS). As the period of the full length of the wavetable
always evenly divides the sample rate, the additional aliasing is largely harmonic in nature. Fold
controls the signal wavefolding.
In many places in the signal path, there are soft clipping stages to mimic analog-style clipping to give
more warmth and complexity to the sounds generated.
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