Instrument spectra blend source and modifier effects, revealing pluck position.

Evidence

An important point to note is that this is the spectrum of the output from the instrument, and therefore it includes the effects of the sound modifiers (e.g., air and plate resonances), so harmonic amplitudes are affected by the sound modifiers as well as the sound source. Also, the fifteenth and twentieth harmonics are nearly 40 dB lower than the low harmonics in amplitude, and therefore background noise will have a greater effect on their amplitudes. The guitar spectrum also suggests particularly clearly a pluck point at approximately one sixth of the string length, given the dips in the amplitudes of the sixth, twelfth and eighteenth harmonics. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1129

Categorization

Category: Causal Relationships

• DEFINE: Explains how reading a guitar’s spectrum can infer the pluck point from harmonic dips — a core psychoacoustic decoding skill.

Related

• Measured instrument spectra blend source harmonics with resonance modifiers (similarity 0.84)
• A stringed instrument’s pluck position can be read from harmonic amplitude dips. (similarity 0.81)
• Plucking position on a string suppresses modes with nodes there (similarity 0.78)
• String instruments naturally produce inharmonic partial spectra. (similarity 0.78)