Real reflections are attenuated enough to tame comb filtering drastically

Evidence

The effect of this is a large reduction of the comb filtering effects that highlevel early reflections cause. This is due to both the reduction in amplitude due to the diffusion and the smoothing of the comb filtering caused by the multiplicity of time delays present in the sound arriving from the diffuser. As these comb filtering effects are thought to be responsible for perturbations of the stereo image (Rodgers, 1981), one should expect improved performance even if the level of the early reflections is slightly higher than the ideal. — David Howard, Jamie Angus, coustics and Psychoacoustics, 2309 (#corroborates, via linked claim)

Categorization

• XREF: connects to: Each open-end reflection filters out high frequencies until the fundamental remains; A time delay of a reflection imprints a comb of enhanced and suppressed frequencies; Ground reflection colors all outdoor speech and creates comb-filter pitch (+8 more)

Related

• Diffuse reflections reduce comb-filtering that perturbs stereo imaging (similarity 0.90)
• The favored reflection conditions measure as comb filtering yet sound pleasing (similarity 0.87)
• Redirecting reflections creates uneven hot spots while absorption shortens reverberation (similarity 0.86)
• Absorbing first reflections cascades to attenuate the whole reflected sound field (similarity 0.84)
• Higher absorption reduces the first-reflection energy that feeds the reverberant field (similarity 0.84)
• Comb-filtering undulations from room reflections move to bass and become inaudible (similarity 0.83)
• Real-room reflections are attenuated and delayed, not equal-level and immediate. (similarity 0.83)
• Engineered diffusers attenuate the specular reflection toward the listener by up to 20 dB (similarity 0.83)
• Ground reflection colors all outdoor speech and creates comb-filter pitch (similarity 0.83)
• Room reflections mitigate the phantom-center comb-filter dip near 2 kHz. (similarity 0.82)
• Console-mounted near-field monitors suffer comb filtering from coaxial reflections (similarity 0.82)
• Diffusers mainly attenuate specific reflections rather than create diffuse fields (similarity 0.82)
• ASW depends most on mid-frequency reflections within the first 80 ms (similarity 0.81)
• Steady-state comb-filter measurements fail to represent how transient sounds are heard (similarity 0.81)
• Early reflections must stay below roughly 15 dB to avoid blurring a stereo image (similarity 0.81)

Broader Connections

• The favored reflection conditions measure as comb filtering yet sound pleasing #corroborates (0.85)
• Diffuse reflections reduce comb-filtering that perturbs stereo imaging #corroborates (0.80) — David Howard, Jamie Angus, coustics and Psychoacoustics, 2309
• Absorbing first reflections cascades to attenuate the whole reflected sound field #corroborates (0.80)
• Redirecting reflections creates uneven hot spots while absorption shortens reverberation #qualifies (0.75)
• Higher absorption reduces the first-reflection energy that feeds the reverberant field #corroborates (0.75) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1763
• Engineered diffusers attenuate the specular reflection toward the listener by up to 20 dB #corroborates (0.72)