Diffusers mainly attenuate specific reflections rather than create diffuse fields

Evidence

If diffusion is not a requirement for listening rooms, why do we use diffusers? They are, or should be, used to attenuate specific reflections by sending most of the energy in the incident sound off in many directions. Whether the scattered sound is a problem is a reasonable concern. A diffuse sound field is not a desirable feature in a sound reproduction venue; the multichannel program should deliver the effect as needed. Fortunately, because of the amount of absorption in these spaces, it cannot exist. — Toole, Floyd E, Sound reproduction- the acoustics and…, 1257

Categorization

• DEFINE: Reframes the purpose of diffusers in listening rooms: targeted reflection attenuation rather than genuine diffusion.
• XREF: Reinforces the thesis that program content, not the room, should produce spatial effects in multichannel reproduction. — connects to: Engineered diffusers attenuate the specular reflection toward the listener by up to 20 dB; Deep broadband diffusers can create a 30 dB immediate reflection drop — Toole, Floyd E, Sound reproduction- the acoustics and…, 1430; Diffusing surfaces may not reduce perceived reflection loudness as expected — Toole, Floyd E, Sound reproduction- the acoustics and…, 655 (+2 more)
• corroborated: 2 independent passages support this claim — Toole, Floyd E, Sound reproduction- the acoustics and…, 1257

Broader Connections

• Engineered diffusers attenuate the specular reflection toward the listener by up to 20 dB #corroborates (0.95)
• Deep broadband diffusers can create a 30 dB immediate reflection drop #corroborates (0.90) — Toole, Floyd E, Sound reproduction- the acoustics and…, 1430
• Diffusing surfaces may not reduce perceived reflection loudness as expected #corroborates (0.85) — Toole, Floyd E, Sound reproduction- the acoustics and…, 655
• Diffuse surfaces make room acoustics degrade gradually away from the sweet spot #complicates (0.70)