Regularly spaced surface bumps diffuse sound only at specific frequencies
Evidence
So, one has a problem: a regular sequence of bumps will diffuse but only at frequencies at which it is an odd multiple of λ 4 . Note also that these fre quencies will depend on the angle of incidence of the incoming wavefront. — David Howard, Jamie Angus, coustics and Psychoacoustics, 2126
Categorization
Category: Causal Relationships
- QUESTION: Curiosity: how do angle-of-incidence dependencies complicate real-world room design where sound arrives from all directions?
Related
- Acoustic diffusion needs surface bumps sized between an eighth and a half wavelength (similarity 0.89)
- Flat surfaces reflect low-frequency sound specularly but scatter high-frequency sound (similarity 0.87)
- How bumps reflect sound depends on bump height relative to wavelength. (similarity 0.87)
- Effective sound diffusion requires bumps sized between an eighth and half a wavelength. (similarity 0.86)
- Any change in surface reflectivity, not just bumps, causes sound diffusion (similarity 0.85)
- Whether a surface reflects or scatters waves depends on roughness relative to wavelength (similarity 0.83)
- Reflection from a bumpy surface depends on bump height relative to wavelength. (similarity 0.83)
- Lower frequencies diffract more around obstacles than higher frequencies do (similarity 0.82)
- Effective sound diffusion demands surface depths proportional to the target wavelength (similarity 0.81)
- Curved surfaces concentrate sound locally while draining power elsewhere in the room (similarity 0.81)
- Sound diffracts strongly only when wavelengths exceed opening size (similarity 0.80)
- Sound bends around obstacles through a process called diffraction (similarity 0.80)
- Reflection and diffraction of sound both depend on object size relative to wavelength (similarity 0.80)
- Element-based acoustic models scale poorly as wavelength shortens (similarity 0.80)
- Lateral diffuse reflections are required for listener enjoyment (similarity 0.79)
Broader Connections
- How bumps reflect sound depends on bump height relative to wavelength.
#expands(0.85) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 2073 - Diffuse surfaces scatter sound hemispherically rather than mirror-like
#expands(0.80) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 2318 - Acoustic diffusion needs surface bumps sized between an eighth and a half wavelength
#qualifies(0.80) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 2071 - Effective sound diffusion demands surface depths proportional to the target wavelength
#corroborates(0.80) — David Howard, Jamie Angus, coustics and Psychoacoustics, 2143 - Diffusing surfaces may not reduce perceived reflection loudness as expected
#complicates(0.75) — Toole, Floyd E, Sound reproduction- the acoustics and…, 655