Inharmonic Audio

...these examples refer to a vast domain opened up by digital synthesis, namely that of inharmonic tones. Most sustained instrumental tones are quasi-periodic, and their frequency components are harmonically related, which stress certain intervals like the octave or the fifth. With the freedom of constructing tones from arbitrary components, one can break the relationship between consonance-dissonance aspects and fixed, privileged intervals.

Jean-Claude Risset Digital Techniques and Sound Structure in Music