A principal organ pipe’s first two harmonics dominate its spectrum

Evidence

The spectrogram shown in Figure 5.1 shows three black horizontal lines, which are the first three harmonics of the principal note (since the frequency axis is linear, they are equally spaced). The first and second harmonics are slightly blacker (and thicker) than the third, reflecting the amplitude difference as shown in Figure 4.17. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1436

Categorization

• XREF: Directly tied to the earlier LTAS data for the same C4 note in Figure 4.17 — a cross-figure, cross-method comparison. — connects to: Organ pipes begin notes one brief harmonic above their sustained pitch — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1446; Chiff-voiced organ pipes begin with the second harmonic leading by about 30 ms — David Howard, Jamie Angus, coustics and Psychoacoustics, 1470; Stopped organ pipes trade space savings for weaker harmonic spectra — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1183 (+15 more)

Broader Connections

• Organ pipes begin notes one brief harmonic above their sustained pitch #qualifies (0.90) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1446
• Chiff-voiced organ pipes begin with the second harmonic leading by about 30 ms #qualifies (0.90) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1470
• An open-open pipe’s modes form a complete harmonic series at integer multiples #expands (0.90)
• Overblowing a pipe jumps its pitch to the next resonator-supported harmonic #qualifies (0.90) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1211
• Open and stopped organ pipes audibly start on different overblown harmonics #qualifies (0.85) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1471
• Pipe organ stops can reinforce non-octave harmonics to reshape timbre #qualifies (0.85)
• Pipe organs function as additive synthesizers by combining harmonics through stops. #expands (0.85) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1551
• Wide organ pipes suppress upper harmonics in their output #contradicts (0.80) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1212
• Organ pipe resonator shape follows construction convenience more than acoustics #expands (0.80) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1180
• Pipe organ stops reinforcing non-octave, non-unison harmonics are called mutation stops #qualifies (0.80) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1534
• Large pipe organs include stops sounding one or two octaves below foundation pitch #expands (0.80)
• Stopped organ pipes trade space savings for weaker harmonic spectra #contradicts (0.75) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1183
• Organ pipes’ timbre arises from resonances cooperating with edge tone #expands (0.75)
• Organ pipes exemplify both reed and flue wind-instrument sound sources #qualifies (0.75) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1133
• Organ flue pipes divide into open-open and open-closed acoustic types #expands (0.75) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1152