All sound can be broken down into individual frequency components, and the lowest frequency component of a sound is called the “fundamental” (all the frequencies above that fundamental frequency are the “partials”). By cleverly setting the relationships of the amplitude and frequencies of the harmonic spectrum, though, you can trick your ear into hearing the pitch of a sound as an octave below the lowest frequency component.
Here, I’ve built a quick demo in Reaktor 6. Listen and see what you think.
Subharmonics are frequencies that are whole-number divisions of a given frequency (in contrast to harmonics, which are whole number multiples of a frequency). While harmonics naturally occur as part of the timbre of a sound, subharmonics, when introduced, sound like distinct pitches, allowing you to create chords of harmonically-related notes.
This tutorial walks you through making a set of subharmonic oscillators and envelope filter like the ones on the Moog Subharmonicon.
In this week’s video, we make a wavefolder in Reaktor, slowly adding features, and testing out some different types of waveforms.
It’s not terribly effective to filter sine waves, since they only consist of a single frequency, but, using a wavefolder, we can add harmonics, and create a rich, customizable sound.
Wavefolding is distortion of a waveform where, when the input amplitude exceeds a threshold, it becomes inverted. This adds harmonics to the sound (specifically odd harmonics), and, by controlling the amount of fold, we can modulate these in real time.