Boosting an upper partial can shift perceived pitch toward that partial’s frequency.

Evidence

This is clearly periodic with period T = 1/f as expected. Since cos(0) = cos(2nπ) = 1, the correlation is large and positive at τ = 0 and every period T thereafter. We show c(τ) for a typical periodic tone in figure 23.10A. Figure 23.10B shows the power spectrum and autocorrelation in A with the fundamental at 100 Hz removed. Last, in C, we see the spectrum and autocorrelation with the fundamental at 100 Hz still removed, but with the second partial at 200 Hz boosted. Now we notice a stronger, but still not dominant, revival at τ = 0.005, although the periodicity is still T = 0.01 second. If the 200 Hz partial towers over all others, we will start to hear a 200 Hz pitch. — Eric J. Heller, Why You Hear What You Hear- An…, 2087

Categorization

• DEFINE: Concretely demonstrates how autocorrelation peaks encode periodicity and how changing partial amplitudes can shift dominance among competing pitch candidates.
• XREF: connects to: Highest common factor of partials encodes perceived pitch — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 857