Most vibrating objects produce inharmonic partials, unlike the ideal string

Evidence

The inharmonic partials (inharmonic meaning that the partial frequencies are not equally spaced) that we find for relatively few beads is typical of vibrating systems. If you bang on a piece of metal, you are not likely to hear a pleasing periodic tone. The string with N beads is inharmonic in a systematic way, with the spacing between adjacent frequencies growing smaller at the top of the spectrum. Typical objects (a string is certainly not typical) will tend to have more jumbled, seemingly unsystematic spectra. We will meet systems with inharmonic partials many times again; they are the norm, not the exception, for vibrating objects. Bells, chimes, and so on have inharmonic partials, but they are carefully crafted through thickness and shape adjustments to give a pleasing tone and a desired pitch (which, as we will see, need correspond to none of the actual mode frequencies). — Eric J. Heller, Why You Hear What You Hear- An…, 805

Categorization

• DEFINE: Defines ‘inharmonic partials’ as partials whose frequencies are not equally spaced.
• CANDY: Nice fact: bells and chimes are carefully shaped so their pitch needn’t match any actual mode frequency.
• XREF: connects to: Real strings produce inharmonic partials whose deviation grows steeply with thickness — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1095