Reaktor/Tutorials/Reaktor as effects processor/LFOs — use waveforms to move parameters
LFOs—Use waveforms to move parameters
A Low Frequency Oscillator is simply a wave-form generator whose waves are moving so slowly that they can be used as a modulation source, instead of so fast that they make a sound (and would be more useful as a sound source for a synth).
You can connect the output of any LFO available in Reaktor, either from the Macro or Module Libraries, or swiped from other instruments and ensembles, via MIDI, to any knob, slider, or other panel control and watch the control move, following the LFO's wave form, which can be one of several common types, including sine, triangle, pulse, random, and others.
The trick is to focus the movement exactly where you want it using the LFO's control settings, its properties and other modules which can change the values and shapes of the waves. Most LFOs are “bi-polar;” that is, their wave-forms travel equally far both above and below zero, creating both positive and negative values. Many knobs, etc., on the other hand, only go from zero to maximum. So, the first thing I set out to build was a Positive-only LFO.
Of course, I didn't have to build this from scratch; I just asked about it in the Reaktor forums, and many ideas and suggestions appeared over night (special thanks to Chris List and John Nowak). And, I later discovered that several LFOs with positive-only settings already exist for the taking... there's one in the Green Matrix synth, for example, which I've used here and included in the downloads; it's hooked up to the Position Slider in the InScanner instrument just described. Let's take a closer look.