Basic overview of the module.
This module is a fully modulatable (up to and including audible frequency modulation) mathematical waveshaper, using a natural Sine function.
Harmonically rich and interesting sounds can be obtained shaping a plain sine wave oscillator with this module.
The Sine accuracy can be selected with the hidden Accurate pin (exact Sine vs. cubic approximation, about half CPU load).
Note: The audible difference is often negligible though.
Plugs:
Input: The audio signal to be modulated.
Sine Frequency: The Sine Frequency plug specifies the sine frequency as the amount of complete cycles per 10 V of input signal. For those who are interested the formula is: V_Out = sin(V_In * Freq * 2PI / 10)
Output: The audio output resulting from the audio input being acted upon by the Sine frequency function. Note: this can reach +/- 10V peak to peak, so will need attenuating in most usage.
Demo structure.
The easiest way to demonstrate this module is with the setup below, where we can have an sine wave audio oscillator feeding the input, and another oscillator set up to run at lower frequencies. If we use a ramp waveform running at about 0.5 Hz we can clearly hear the effect as the effect of the Sine Modulation value fading away. It sounds a bit like a filter which is almost on the point of self oscillation being swept through its cutoff range, but without any filtering effect.
The best way to learn how it sounds is experiment.
The only point of note is the +5 V offset on Input 1 of the Level Adj module, this is to keep the modulation voltage positive at all times.
Note: The one oscillator waveform that doesn’t really work either as source or modulation is noise… this just results in slightly distorted noise!
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