Standing waves can form without two bounding reflectors
Evidence
Strictly speaking the standing waves we are discussing here should be called resonant modes. This is because it is possible to set up a standing wave without the use of two boundaries. For example, one could use two loudspeakers spaced apart and no boundaries to get a standing wave at discrete frequencies. One can do the same with one loudspeaker, or sound source, and one boundary. — David Howard, Jamie Angus, coustics and Psychoacoustics, 397
Categorization
Category: Contrarian or Surprising Claims
- DEFINE: Distinguishes standing waves (which need only sources and one boundary) from resonant modes.
Related
- Standing waves are a subclass of the more general phenomenon called resonant modes (similarity 0.91)
- Sound waves reflecting between two boundaries can form standing waves (similarity 0.89)
- Standing waves arise from counter-propagating reflections with no net energy flow (similarity 0.89)
- Opposing waves cancel only momentarily because energy persists in kinetic form (similarity 0.85)
- A standing wave is still moving at normal speed while appearing stationary (similarity 0.83)
- Standing waves form when wavelengths match room dimensions (similarity 0.82)
- Acoustic waves reflect at discontinuities in tract area (similarity 0.82)
- Low frequencies cannot form diffuse fields because boundaries create standing waves (similarity 0.81)
- Confinement or wave return, not mere amplitude, is essential to resonance (similarity 0.81)
- Waves transitioning from bounded to unbounded space create interfering reflections (similarity 0.81)
- Standing waves occur at all multiples of the lowest resonant frequency (similarity 0.81)
- Bounded sound waves change impedance with tube area, causing reflections (similarity 0.80)
- Standing waves create loudness dips at room midpoints (similarity 0.79)
- Standing-wave thinking applies only at low frequencies in small rooms (similarity 0.79)
- Standing waves occur at all integer multiples of a fundamental frequency (similarity 0.78)