Harmonic Fantasy No. 4 plays melodies among the harmonic partials above the sixteenth to reflect the harmony of the passage, and it also uses instruments that play the sound as a complex envelope or as individually attacked components. This work also has passages where only partials above the eighth (three octaves above the fundamental) are used, where the identification of the fundamental frequency is not always evident, and it also has passages that play the partial sequence more than once through the course of the tone. The work was composed in the Fall of 2018 and generated by the Csound program.