Nearby reflecting surfaces constructively pile up wave reflections to amplify sound
Evidence
Proximity resonance results when a source of sound experiences almost immediate and constructive interference, due to some type of confinement or other nearby in-phase source (see, for example, sections 7.1 and 7.2). The confinement reflection must preserve the sign of the wave; otherwise, the reflection will suppress the source by destructive interference, or anti resonance. Proximity resonance makes possible large amplifications in the throat of horns (section 7.3) and the reproducer of a gramophone (figure 7.6), where many reflections from close-by surfaces pile up constructively and lead to large enhancements of the amplitude and the power. — Eric J. Heller, Why You Hear What You Hear- An…, 886
Categorization
Category: Definitional Content
- DEFINE: Defines proximity resonance as a distinct mechanism from driven-oscillator resonance, grounded in constructive interference.
Related
- Confinement reflections amplify sources only when wave sign is preserved (similarity 0.93)
- Nearby reflective surfaces can load a source and boost its output (similarity 0.85)
- Resonant reflections raise impedance in throats and reproducers (similarity 0.82)
- Reflecting surfaces within an eighth wavelength amplify a source via proximity resonance (similarity 0.81)
- Throat chamber echoes raise impedance by in-phase amplitude buildup (similarity 0.80)
- Proximity resonance in gramophones is the same gatekeeper effect as trumpet mouthpieces (similarity 0.80)
- Horn loudspeakers amplify sound through proximity resonance in a narrow throat (similarity 0.79)
- Reflections from a nearby hard wall can double the sound amplitude toward the listener (similarity 0.79)
- Reflections increase sensitivity to low and mid-Q resonances in reproduced sound (similarity 0.79)
- Ṣafī al-Dīn described sound self-amplification via constructive interference (similarity 0.79)
- Resonance requires round-trip reflections arriving in phase with the source (similarity 0.79)
- Sound near walls or large vessels is enhanced by scattering regardless of resonator tuning (similarity 0.79)
- A single sound source near a reflecting surface creates interference via an image source (similarity 0.79)
- Resonance requires confinement of previously emitted amplitude (similarity 0.78)
- Dipole sources amplify through near-field capture, phase shift, and reemission by a resonator (similarity 0.78)
Broader Connections
- Absorbing first reflections cascades to attenuate the whole reflected sound field
#complicates(0.88) — Toole, Floyd E, Sound reproduction- the acoustics and…, 1258