Sound waves reflecting between two boundaries can form standing waves
Evidence
Standing waves occur when sound waves bounce between reflecting surfaces. The simplest system in which this can occur consists of two reflecting boundaries, as shown in Figure 1.30. In this system, the sound wave shuttles backward and forward between the two reflecting surfaces. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 386
Categorization
- DEFINE: Introduces the standing-wave concept via the two-reflector model.
- corroborated: 2 independent passages support this claim — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 386
- XREF: connects to: Acoustic waves reflect at discontinuities in tract area; Standing waves arise from counter-propagating reflections with no net energy flow; Bounded sound waves change impedance with tube area, causing reflections — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 174 (+14 more)
Broader Connections
- Standing waves can form without two bounding reflectors
#qualifies(0.90) - Standing waves arise when wall spacing equals half-wavelength multiples
#expands(0.88) - Standing waves are a subclass of the more general phenomenon called resonant modes
#expands(0.82) - Supported standing-wave frequencies in bounded systems occur at odd multiples of the lowest
#expands(0.82) - Pressure nodes and antinodes structure inside standing waves have complementary velocity counterparts
#expands(0.80) - Acoustic standing waves are termed modes with numbered order by frequency
#expands(0.78) - Standing waves create loudness dips at room midpoints
#expands(0.78) — Toole, Floyd E, Sound reproduction- the acoustics and…, 1020 - Low frequencies cannot form diffuse fields because boundaries create standing waves
#expands(0.75) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1947 - A single sound source near a reflecting surface creates interference via an image source
#expands(0.75) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 366 - Flat surfaces reflect low-frequency sound specularly but scatter high-frequency sound
#expands(0.72) - Waves transitioning from bounded to unbounded space create interfering reflections
#expands(0.70)