Two Models: Frequency Shifter and Ring Modulator
The frequency shifter model shifts each frequency partial by an equal number of hertz. Because the spacing between partials stays constant while their ratios change, the result drifts away from a clear pitch center as the amount increases.
The ring modulator model uses a 2× oversampled sine oscillator as a multiplier on the input signal. It produces a new spectrum with partials shifted both up and down. Sinevibes describes the result as more atonal and metallic, with a bell-like character.






