Real strings’ slightly mistuned partials are a loved feature, not a flaw.

Evidence

A string is essentially a one-dimensional object. We will find that the ideal string possesses a perfectly harmonic (equally spaced in frequency; all frequencies an integer multiple of the fundamental) series of modes. Real strings have some thickness, ruining the perfectly harmonic frequencies we shall derive here. Far from a bug, the mistuned partials of real strings are a feature that we have grown to love and expect. A piano sounds artificial without them. — Eric J. Heller, Why You Hear What You Hear- An…, 762

Categorization

• DEFINE: Defines harmonic vs. inharmonic partial series and explains why real instruments deviate from the ideal.
• XREF: Connects directly to the piano-voicing literature and to why synthetic/electronic instruments are sometimes detectable as ‘artificial.’
• SEED: Possible essay: ‘The beloved imperfection’ — why we prefer slightly inharmonic piano partials over mathematically perfect ones, and what that says about perceptual preference for entropy.