Some Effects of Inharmonic Partials on Interval Perception

We have explored some of the effects of tuning intervals with inharmonic partials. The tones that composed the intervals had partials whose spacing is given by ffₙ = KAlog 2n/1wherefₙ is the frequency of the wth partial and K = 2ɸ/Aɸ. We suggest that subjects can successfully (internally) assign a pitch to tones with a structured departure from harmonicity. We find that subjects appear to process intervals with nearly harmonic stimuli (A = 1.9-2.1) in a manner that supports the "best fit" pattern recognition theories of pitch perception. Subject perception of intervals whose component tones were stretched (A > 2.1) is best accounted for by noting the nature of auditory spectral resolution and by interval memory mechanisms. The results imply that temporal synchrony of harmonics becomes increasingly important to interval integrity after A= 2.1 and that the strength of the impression of conventional intervals is dependent on temporal synchrony.