Cylindrical stopped-pipe bores support only odd-numbered modes, forcing extra finger holes

Evidence

In a complete brass instrument, it is possible through the use of an appropriately shaped bell, mouthpiece and mouthpipe to construct an instrument whose modes are frequency shifted from the odd-only modes of a stopped cylindrical pipe to being very close to a complete harmonic series. In practice, the result is a harmonic series in which all modes are within a few percent of being integer multiples of a common lower-frequency value except for the first mode itself, which is well below that lower-frequency value common to the higher modes, and therefore it is not harmonically related to them. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1250 (#expands, via linked claim)

If a pipe is overblown, its f0 jumps to the next higher mode that the resonator can support: up one octave to the second harmonic for an open pipe, and up an octave and a fifth to the third harmonic for the stopped pipe. — David Howard, Jamie Angus, coustics and Psychoacoustics, 1211 (#expands, via linked claim)

Categorization

  • XREF: connects to: One closed and one open pipe end supports only odd quarter-wavelength standing waves; Brass instrument design transforms odd-only pipe modes into a near-complete harmonic series — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1250; A closed pipe’s first mode sits an octave below an open pipe’s (+5 more)

Broader Connections