A method of manipulating a complex waveform by considering the harmonic and partial frequencies as moving targets over time in both amplitude and frequency and adjusting the moving targets by moving modifiers in both amplitude and frequency. The manipulation of harmonic frequencies and the synthesis of harmonic frequencies are based on the harmonic rank. The modifiers move with the movement of the frequencies based on rank. Harmonic transformation modifies, by rank, the waveform from one source to a waveform of a second or target source. Harmonics and other partials accentuation identifies each of the frequencies and its relationship to adjacent frequencies as well as fixed or moving thresholds and make the appropriate adjustment. Interpolation is also disclosed as well as models which imitate natural harmonics.