an inharmonic sound is a complex sound in which the sound energy is not distributed across the spectrum in a mathmatically ordered fashion (sound energy partials are distributed, relative to a fundamental, in non-whole number ratios, for example f1.84, f2.76, f3.14, f4.15). Inharmonic sounds contain partials of sound energy concentrated at specific frequencies within the sound spectrum but these partials do not have a simple mathmatical relationship (for example: they are not whole number multiples of a fundamental frequency). Inharmonic sounds can be pitched (for example: bells).
