Percussion excitation is a short impulse rather than a sustained tone

Evidence

Similarly, grain is a special type of internal fluctuation, one with a regular modulatory effect. It is accordingly contrasted with transients, which are isolated or irregular fluctuations. Grain gives texture; it roughens up the surface of the sound and its effects consist of tremolo (amplitude modulation) or vibrato (frequency modulation). — Schafer, Murray R, The Soundscape- Our Sonic Environment…, 466 (#qualifies, via linked claim)

In order that notes can be played which have a clearly perceived pitch on percussion instruments such as the xylophone, marimba and vibraphone—with playing ranges from C5 (523 Hz) to C8 (4186 Hz), A2 (110 Hz) to C7 (2093 Hz) and F3 (175 Hz) to F6 (1397 Hz), respectively—the bars are shaped with an arch on their undersides to tune the modes to be close to harmonics of the first mode. In the marimba and vibraphone, the second mode is tuned to two octaves above the first mode, and in the xylophone, it is tuned to a twelfth above the first mode. These instruments have resonators, which consist of a tube closed at one end, mounted under each bar. The first mode of these resonators is tuned to the f0 of the bar to enhance its loudness, and therefore the length of the resonator is a quarter of the wavelength of f0 (see Equation 1.36). — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1287 (#complicates, via linked claim)

Categorization

• XREF: connects to: Sustained field activity does not track melodic structure.; Where you strike a percussion instrument governs which modes sound; Nonharmonic natural modes give struck percussion instruments their clangy identity (+5 more)

Broader Connections

• Nonharmonic natural modes give struck percussion instruments their clangy identity #expands (0.85)
• Sound grain is regular modulation, opposed to isolated transients #qualifies (0.80) — Schafer, Murray R, The Soundscape- Our Sonic Environment…, 466
• Percussion bars are shaped to tune their modes toward harmonic ratios #complicates (0.80) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1287
• Drum-head construction and excitation method define each drum’s basic acoustics #expands (0.75)