Vowel identity is carried by upper partial tones, not fundamentals

Evidence

Raise the dampers of a pianoforte so that all the strings can vibrate freely, then sing the vowel ahh in father loudly to any note of the piano, directing the voice to the sounding board; the sympathetic resonance of the strings directly re-echoes the same ahh. On singing oe in toe, the same oe is re-echoed…. The experiment does not succeed so well if the damper is removed only from the note on which the vowels are sung. The vowel character of the echo arises from the re-echoing of those upper partial tones which characterize the vowels. These, however, will echo better and more clearly when their corresponding higher strings are free and can vibrate sympathetically. In this case, then, in the last resort, the musical effect of the resonance is compounded of the tones of several strings, and several separate partial tones combine to produce a musical tone of a peculiar quality. — Eric J. Heller, Why You Hear What You Hear- An…, 1986

Categorization

• SHARE: Send to a musician or piano technician friend — a lovely concrete demonstration that vowel timbre lives in harmonics, re-echoed sympathetically by a free-strung piano.
• XREF: connects to: Vowel identification depends on formant peaks being representable in the output spectrum. — David Howard, Jamie Angus, coustics and Psychoacoustics, 1368